Term
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Definition
| Renal agenesis is failure of development of the renal anlage, resulting in a complete absence of the kidney. Renal agenesis may be bilateral or unilateral |
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Term
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Definition
| Bilateral renal agenesis is a rare anomaly resulting in death in utero or soon after delivery. Infants have renal failure associated with characteristic facial features: wide-set eyes and prominent inner canthi, a broad, flattened nose, large and low-set ears, and a receding chin (Potter facies). |
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Term
| Unilateral renal agenesis |
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Definition
| Unilateral renal agenesis is more common, occurring in 0.1% of the population. It is asymptomatic because the single kidney is capable of subserving normal renal function. The frequency of unilateral renal agenesis makes confirmation of the presence of two kidneys obligatory before nephrectomy or even biopsy is performed. |
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Term
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Definition
| Horseshoe kidney is abnormal fusion of the two organs, with the lower poles fused across the midline by a broad band of renal tissue. It occurs in 0.4% of individuals. The ureters pass anterior to the isthmus of the horseshoe kidney and may be narrowed. Most patients are asymptomatic; there is a higher incidence of urinary infection and renal calculi. |
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Term
| Polycystic kidney disease |
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Definition
| Polycystic kidney disease is hereditary and bilateral. The autosomal recessive polycystic kidney disease (ARPKD), previously called "infantile" PKD, has numerous small cysts that only arise from the collecting ducts and result in bilateral symmetrical enlargement of the kidneys. |
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Term
| The autosomal dominant PKD |
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Definition
| The autosomal dominant PKD, previously called "adult" PKD, has cysts arising from all areas of the nephron, which are usually larger and more variable in size than the ARPKD cysts. |
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Term
| Polycystic kidney disease |
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Definition
| The diagnosis is often made during a workup for hypertension or uremia discovered in the third to sixth decades. Hematuria with or without flank pain is a common finding. An intravenous urogram will reveal the enlarged kidneys, with marked elongation of the calices, which are compressed by large cysts |
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Term
| Nephritic Syndrome—Clinical Features |
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Definition
Hematuria
Red blood cell (RBC) casts and dysmorphic/fragmented RBCs in urinary sediment
Oliguria
Proteinuria
Hypoalbuminemia
Edema, generalized
Hypertension |
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Term
| Nephrotic Syndrome—Clinical Features |
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Definition
Proteinuria
Hypoalbuminemia
Edema, generalized
Hyperlipidemia
Lipiduria with lipid casts in urinary sediment |
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Term
| Acute Poststreptococcal Proliferative Glomerulonephritis |
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Definition
Organisms other than beta-hemolytic streptococci may cause glomerulonephritis (nonstreptococcal acute glomerulonephritis). Convincing data exist to incriminate Staphylococcus aureus, Streptococcus pneumoniae, Neisseria meningitidis, the plasmodia of malaria, Toxoplasma gondii, and some viruses.
Immune complexes formed between antigens in the organism and host antibody are deposited in the glomerular filtration membrane, fix complement, and lead to inflammation. The specific streptococcal antigen involved in forming circulating immune complexes is not known. |
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Term
| MEMBRANOUS GLOMERULONEPHRITIS |
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Definition
Immunofluorescence shows granular deposits of IgG and C3 corresponding to the subepithelial deposits.
Clinically, patients with membranous glomerulonephritis present with either the nephrotic syndrome or asymptomatic proteinuria. The proteinuria is nonselective. Hematuria is absent in the early stage of the idiopathic disease.
Most patients have a slow progression to chronic renal failure. |
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Term
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Definition
Renal artery stenosis is uncommon but is an important disease in that it represents a potentially treatable form of hypertension. There are several causes.
(1) Atherosclerosis is the most common cause, particularly in older patients.
(2) Fibromuscular dysplasia of the renal artery is a rare condition of unknown cause, occurring in younger patients (20–40 years of age), particularly in women. It is characterized by unilateral or bilateral single or multiple constrictions of the renal arterial wall, caused by fibromuscular thickening of the media or, more rarely, the intima. Other arteries may be involved. Surgery is curative if the pathologic process is localized.
(3) Posttransplantation stenosis occurs in 10–20% of patients after renal transplantation, most commonly as a manifestation of rejection. Intimal thickening follows immunoglobulin deposition in donor vessel walls. Less commonly, the stenosis occurs at the site of anastomosis. |
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Term
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Definition
Calcium stones—calcium phosphate or calcium oxalate stones (75%)
Struvite stones (15%)
Uric acid stones (5%)
Cystine stones (1%) |
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Term
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Definition
Tumor of infancy and childhood
Composed of immature cells resembling renal blastema
Related in some cases to deletion or mutation of tumor suppressor gene WT-1
May be familial or bilateral in 10% cases
Good prognosis when surgery is combined with chemotherapy |
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Term
| Carcinoma of the Urinary Bladder |
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Definition
Most common cancer of the urinary tract—52,000 new cases per year in the United States and 10,000 cancer-related deaths
Most tumors are transitional carcinomas but may be squamous or adenocarcinomas
Variable prognosis—depends on the grade and stage of the tumor |
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Term
| Urinary Bladder Carcinoma—Clinical Features |
|
Definition
Hematuria
Dysuria
Lower abdominal pain
Diagnosis made on urine cytology and cystoscopic biopsy
Grade I tumors localized to mucosa—98% 5-year survival but tend to recur
Grade III tumors with metastases—15% 5-year survival |
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Term
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Definition
Acute epididymo-orchitis is a common infection caused by bacteria that reach the epididymis from the urethra. Escherichia coli, gonococci, and chlamydiae are common culprits. Organisms reach the epididymis via the vas deferens secondary to reflux of infected urine from the prostatic urethra, or via the lymphatics of the spermatic cord. Acute pyogenic inflammation of the epididymis ensues, commonly extending into the testis.
Clinical Features
patients present with acute onset of fever, pain, and tenderness and redness of the scrotum extending along the spermatic cord. Resolution occurs rapidly with specific antibiotic therapy
Complications
(1) fibrosis leading to obstruction of the epididymis, resulting in sterility only in those cases where both sides are affected;
(2) vascular compromise, leading rarely to infarction of the testis; and
(3) abscess formation in the scrotum |
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Term
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Definition
Torsion of the testis is a common condition caused by twisting of the spermatic cord, leading to vascular obstruction.
Abnormalities of the testis or its ligaments are predisposing factors.
Torsion occurs commonly in incompletely descended testes.
edema, hemorrhage, and finally venous infarction of the testis.
Clinical Features
sudden onset of severe pain with marked swelling of the scrotum
The testis is intensely tender.
Orchiectomy is required in cases that have progressed to necrosis of testicular tissue. |
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Term
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Definition
characterized by nests of uniform large round cells that have distinct cell membranes, centrally placed nuclei, prominent nucleoli, and clear cytoplasm containing abundant glycogen;
these cells resemble the primary spermatocytes in the seminiferous tubule. |
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Term
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Definition
The presence of cytotrophoblastic and syncytiotrophoblastic giant cells, arranged in a manner resembling their relationship in chorionic villi, is characteristic.
There is almost always extensive hemorrhage.
The syncytiotrophoblastic cells secrete human chorionic gonadotropin (hCG) and stain positively for hCG |
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Term
| Interstitial (Leydig) cell tumors |
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Definition
occur mainly in children and young adults
often produce androgens, causing precocious puberty in children. More rarely, they secrete estrogens.
Microscopically, there are sheets of large cells resembling interstitial cells
The biologic behavior of these tumors is usually benign, but about 10% are malignant |
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Term
| Prostate Carcinoma—Etiology and Pathogenesis |
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Definition
The cause remains unknown.
No major risk factors have been identified.
Hormonal influences—testosterone plays a role in the pathogenesis.
There are racial differences in the incidence.
Incidence among Americans of various origin is as follows: African > European > East Asian. |
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Term
| Prostate Carcinoma-Clinicopathologic Features |
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Definition
The tumor most often is located in peripheral parts of the prostate.
Metastases to local lymph nodes and vertebrae, other bones, and internal organs are noted.
Bone metastases may be osteolytic or osteoblastic (serum alkaline phosphatase).
Prostate-specific antigen (PSA) is a good marker of prostate carcinoma, but it has low specificity. |
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Term
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Definition
Primary stage
Chancre and inguinal lymphadenopathy
Secondary stage
Systemic spread of spirochetes; occurs 2 months to 2 years later
Systemic symptoms, macular rash, condyloma latum, hepatitis, other internal organ inflammations
Tertiary stage
CNS and cardiovascular lesions; occurs 2 to 20 years later |
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Term
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Definition
one of the most common sexually transmitted diseases
Gonorrhea is caused by the gram-negative diplococcus, Neisseria gonorrhoeae. The organism infects chiefly the urethra in the male, producing acute urethritis. In the female, the cervix is the main site of infection. |
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Term
| Gonorrhea-Clinical Features & Diagnosis |
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Definition
In men, the common presentation is with dysuria and purulent urethral discharge
In both sexes, gonorrhea may be asymptomatic, constituting a source of apparently healthy carriers, who represent the main reason why the disease is difficult to control |
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Term
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Definition
Related to human papillomavirus infection
Preceded by CIN (dysplasia progressing to carcinoma in situ and invasive carcinoma)
Histologically—squamous cell carcinoma
Early detection by Pap smear
Variable prognosis—depends on the stage of the tumor |
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Term
| Endometrial Adenocarcinoma |
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Definition
Related to hyperestrinism
May be preceded by endometrial hyperplasia
Occurs in perimenopausal and postmenopausal (older) women
Histologically—adenocarcinoma
Variable prognosis—depends on the stage and to a lesser extent on the grade of the tumor |
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Term
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Definition
Foci of endometrium found outside the uterus
Most often located on the ovary and pelvic peritoneum
Very common disease, clinically causing:
Cyclic pain
Infertility |
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Term
| Polycystic Ovary Syndrome |
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Definition
Polycystic ovary syndrome is characterized by
(1) bilaterally enlarged ovaries;
(2) multiple follicular cysts in the outer, subcapsular region;
(3) absence of corpora lutea (resulting from failure of ovulation); and
(4) hyperplastic ovarian stroma with thickening of the capsule
Causes?
The cause of polycystic disease is probably abnormal secretion of pituitary gonadotropins;
the normal luteinizing hormone (LH) surge that causes ovulation is lacking, and continuous FSH and LH stimulation leads to the development of multiple follicular cysts. |
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Term
| Polycystic Ovary Syndrome-Clinical Features |
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Definition
Clinical Features
(1) amenorrhea, infertility, and virilism
(2) excess androgen secretion (usually androstenedione);
(3) normal or elevated estrogen levels, which may cause endometrial hyperplasia and abnormal uterine bleeding (menorrhagia); and
(4) an increased incidence of endometrial carcinoma. |
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Term
| Polycystic Ovary Syndrome-Treatment |
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Definition
clomiphene, which stimulates ovulation, is effective;
surgical wedge resection of the ovary, which was standard treatment in the past, is now rarely needed. |
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Term
| Granulosa-Theca Cell Tumors |
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Definition
Granulosa-theca cell tumors are derived from the follicular epithelium of the primordial follicles
most frequently seen in postmenopausal women
Granulosa-theca cell tumors typically secrete estrogens, which produce hyperplasia of the endometrium and predispose to endometrial adenocarcinoma.
Abnormal uterine bleeding is the most common mode of presentation. |
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Term
| Pathology of Implantation |
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Definition
Ectopic pregnancy
In spite of the abnormal implantation site, the ovum develops normally in the first few weeks, forming a placenta, an embryo, and an amniotic sac. Later development is greatly impeded by the lack of space, poor vascular supply, and limited placental size.
Rupture of the tube containing the pregnancy frequently occurs 2–6 weeks after fertilization, causing massive, potentially fatal intraperitoneal hemorrhage
In most cases, the released embryo dies soon after tubal rupture
Clinical Features
Patients with tubal pregnancy present with evidence of early pregnancy such as a missed menstrual period, vomiting of pregnancy, or a positive pregnancy test. This is associated with an absence of appropriate uterine enlargement and the presence of a tender mass in the adnexa, representing the expanded uterine tube.
Rupture of a tubal pregnancy produces severe abdominal pain and intraperitoneal bleeding, often rapid and severe. The presence of blood in the peritoneal cavity can be confirmed by aspiration or laparoscopy. Many patients are in a state of hypovolemic shock at the time of presentation. |
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Term
| Pathology of Placentation-Placenta previa |
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Definition
The fertilized ovum normally implants in the fundus, and the placenta forms in that location. Abnormally low implantation may lead to formation of the placenta in the lower uterine segment. When the placenta is formed over the internal os
Placenta previa causes problems only in late pregnancy, chiefly at the onset of labor. Uterine contractions in the first stage of labor cause effacement, stretching, and dilation of the cervix, leading to premature separation of the placenta previa, which results in bleeding, often severe, at the onset of labor (antepartum hemorrhage |
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Term
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Definition
| Placenta accreta is absence of a plane of separation between the placental villi and myometrium. The placenta fails to separate in labor, leading to severe postpartum hemorrhage |
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Term
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Definition
Preeclampsia—triad of hypertension, edema, and proteinuria
Eclampsia—all of the above plus seizures
_________________________________
Note: Common!
Found in 6% of pregnancies; usually mild.
More common in primarius women than in later pregnancies. |
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Term
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Definition
| Preeclampsia—triad of hypertension, edema, and proteinuria |
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Term
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Definition
triad of hypertension, edema, and proteinuria
Eclampsia—all of the above plus seizures
_________________________________ |
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Term
| Risk Factors of Carcinoma of the Breast |
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Definition
Sex—female > male
Genetic factors—family history, BRCA-1 and BRCA-2
Race—white > Africans > East Asians
Age—tumor rare before puberty
Hormones—exogenous estrogen
Premalignant breast changes—intraductal papillomatosis and atypical intraductal hyperplasia
Other cancers—ovary, uterus, or breast |
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Term
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Definition
Multifactorial disease characterized by absolute reduction of the total bone mass
Age related—in those older than 85 years, one third have osteoporosis
Women > men, especially after menopause
Etiologically subdivided into two groups:
Primary osteoporosis—cause unknown
Secondary—related to another disease |
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Term
| Pathogenesis of Primary Osteoporosis |
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Definition
Etiology unknown, but certain factors are known to predispose to osteoporosis
Low initial bone mass (“small frame”)
Bad dietary habits, smoking
Hormones (e.g., early menopause)
Age-related changes in the metabolism |
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Term
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Definition
Common chronic disease of unknown etiology characterized by irregular restructuring of bone and subsequent thickening and deformities of bones
Diagnosis made radiologically
Three phases
Destructive phase
Mixed phase
Osteosclerotic phase |
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Term
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Definition
(1) In the first stage, there is irregular osteoclastic resorption of bone;
(2) In the second stage, osteoblasts react by actively laying down new bone, which balances the osteolysis and maintains the total bone volume. The disease can be recognized at this stage by the irregular manner in which osteoblasts lay down trabeculae. The new bone is highly vascular;
(3) Finally, there is a sclerotic phase in which osteoblastic activity is greatly in excess of osteoclastic resorption, leading to marked thickening of bony trabeculae and cortex |
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Term
| Osteoarthritis—Degenerative Joint Disease (DJD) |
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Definition
Most common joint disease
Disease of old age
Affects weight-bearing big joints but also small joints of hands and feet
Classified as:
Primary—cause unknown or multifactorial
Secondary—related to another disease |
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Term
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Definition
Crepitus is a characteristic feature—a grating sound produced by friction between adjacent areas of exposed subchondral bone.
Osteophytes may be visible clinically—as bony masses such as those that occur over affected distal interphalangeal joints (Heberden's nodes) |
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Term
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Definition
Chronic systemic disease of unknown etiology characterized by the following:
Chronic, symmetric inflammation of joints
proximal interphalangeal joints
Involved joints are swollen, painful, and stiff. Stiffness is maximal in the morning after the joint has been inactive during the night
Significant, but not diagnostic, laboratory findings indicative of immune disorder
Variable extra-articular findings |
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Term
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Definition
Common systemic metabolic disorder often affecting the joints
Hyperuricemia—deposition of urate crystals in tissues; inflammation of joints
Podagra (swelling and pain of first metatarsophalangeal joint of the foot)
Subcutaneous tophi—uric acid nodules
Uric acid urinary stones |
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Term
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Definition
Acute gout—acute attack of joint pain, swelling, and inflammation
Chronic gout—tophi, deposits of uric acid crystals in internal organ, urinary stones |
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Term
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Definition
Autoimmune disease involving the neuromuscular junction (NMJ)
More common in women than in men
Cause unknown
In the younger age group, associated with enlargement of the thymus
Hyperplasia or neoplasia (thymoma)
Striated muscles histologically normal |
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Term
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Definition
Reduced number of surface receptor sites for acetylcholine at the motor neural plate
Easy fatigability and muscular weakness
Small extraocular muscles and facial muscles most often involved
Ptosis, diplopia, easy fatigability on reading, facial muscle weakness, inability to chew; all muscles may become affected |
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Term
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Definition
Diagnosis
Clinical findings
Anticholinesterase test
Electromyography
Serologic testing for antibodies
Treatment—symptomatic
Disease incurable |
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Term
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Definition
Genetic defects inherited as mendelian traits
Primary muscle cell pathology
A progressive course and symptoms related to muscle wasting |
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Term
| Duchenne-type Muscular Dystrophy |
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Definition
Most common muscular dystrophy
Caused by deficiency of dystrophin
Dystrophin holds together other structural proteins, linking them to the cell membrane |
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Term
| Duchenne-type Muscular Dystrophy |
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Definition
Degeneration of skeletal muscle cells with ensuing muscle weakness
Sex-linked recessive disease
Occurs only in boys
Mothers asymptomatic
Milder form—Becker’s dystrophy |
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Term
| Duchenne-type Muscular Dystrophy |
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Definition
In the early stages, individual muscle cell degeneration and loss occur.
The abnormal muscle cells have an irregular shape, granularity of cytoplasm, and centrally located nuclei.
Muscle cell loss is progressive.
Compensatory hypertrophy of viable fibers occurs.
There is ingrowth of fibrous tissue and fat cells. |
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Term
| Duchenne-type Muscular Dystrophy |
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Definition
Appearance of symptoms in preschool children
Weakness of the weight-carrying muscles of the pelvic girdle and lower extremities
Difficulty getting up from a squatting position
Deformed legs, inability to keep legs straight, contractures and deformities of the extremities
Pulmonary infections, heart failure, anemia, reduced intelligence
Early death—usually in late teens or early 20s |
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Term
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Definition
Second most common genetic muscle disease
Autosomal dominant
Triple nucleotide repeat
Myotonia, “hatchet face,” weakness of eye muscles, systemic symptoms |
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Term
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Definition
Recent research has identified many of the central mechanisms that underlie abnormal nociceptive processing in fibromyalgia, including recognition of discrete abnormalities in pro-nociception and anti-nociception pathways, serotonin- and dopamine-related genes, and dysregulation of the stress response system.
The principal effectors of the stress response system (hypothalamic-pituitary-adrenocortical axis and the sympathetic nervous system) become activated in pain states. Although these effectors are normally adaptive, they may become maladaptive in chronic pain syndromes, thereby contributing to diffuse aching pain, fatigue, poor sleep, low mood and anxiety, and flulike illness |
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Term
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Definition
Psychological variables clearly operative in fibromyalgia include pain beliefs and attributions; hypervigilance (expectancy);
active and passive coping strategies;
perceived self-efficacy for pain control;
mood, depression, and anxiety;
personality traits and disorders; and pain behaviors.
Certain environmental and sociocultural variables also contribute to chronic diffuse pain, such as a history of poor health in parents; parental pain history; poor family environment; and childhood abuse, particularly sexual abuse. |
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Term
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Definition
SYMPTOMS AND SIGNS
The hallmark of fibromyalgia is widespread pain (above and below the waist and on both sides of the body) for longer than 3 months.
Pain is described as "exhausting," "miserable," or "unbearable."
The pain often radiates diffusely from the axial skeleton over large areas of the body, primarily in muscles.
Arthralgias may be present together with a subjective sense of joint swelling.
Synovitis is not confirmed by physical examination unless another coexisting rheumatic disease is present.
Morning stiffness may be prominent.
The patient may complain that a light touch or even a breeze is unpleasant (allodynia, defined as pain with stimulation that should not be painful).
The skin may "burn."
Nondermatomal paresthesias are common |
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Term
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Definition
WHEN TO REFER TO A SPECIALIST
Referral to a rheumatologist familiar with fibromyalgia is appropriate when the diagnosis is unclear, when response to therapy is inadequate, and when comorbid musculoskeletal or autoimmune conditions are present.
Psychiatric referral is indicated when significant psychiatric comorbidity is present and is essential for severe depression with suicidal ideation and for comorbid psychosis. Psychotherapeutic counseling is helpful for many patients. |
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Term
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Definition
Between the skull and the dura
Rupture of middle meningeal artery
Coma
Invariably lethal if unrecognized |
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Term
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Definition
Located between the dura and the arachnoid
Source of bleeding—ruptured bridging veins
Nonspecific symptoms (e.g., headache) caused by increased intracranial pressure |
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Term
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Definition
Located between the arachnoid and the pia layer of the meninges
Caused by:
Traumatic contusion of the brain
Rupture of congenital (berry) aneurysms
High mortality |
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Term
|
Definition
Caused by thrombotic occlusion and thromboemboli
Encephalomalacia
Pale infarct or hemorrhagic infarct
Surrounding brain tissue that is edematous
Fluid-filled cavity (“pseudocyst”)
Clinical presentation as stroke (e.g., contralateral hemiplegia, sensory loss, global aphasia, drowsiness, stupor, coma) |
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Term
|
Definition
Caused by arterial hypertension
Basal ganglia
Well-circumscribed hematoma
Clinical features possibly resembling those of cerebral infarction |
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Term
|
Definition
Demyelinating disease
Women affected twice as often as men
Genetic factors
Oligoclonal T-cell populations in the brain
IgG in CSF composed of oligoclonal bands |
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Term
|
Definition
Chronic disease
Episodes of exacerbation and remission of neurologic symptoms
Sensory abnormalities
Loss of sensitization of touch
Motor abnormalities
Muscle weakness, unsteady gait, incoordination of movements, sphincter abnormalities
Unpredictable course |
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Term
|
Definition
Wernicke-Korsakoff syndrome
Uncoordinated movements
Progressive mental deterioration, loss of memory, inability to concentrate, irritability
Subdural hematoma, pontine myelinolysis
Delirium tremens |
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Term
|
Definition
Unknown etiology
Genetic factors—Down’s syndrome
Atrophy of the cortical parts of the frontal and temporal parts of the brain
Disease of older people (>70 years)
Dementia—progressive loss of cognitive functions and a functional decline (loss of memory predominates) |
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Term
|
Definition
Gross examination
The brain appears atrophic and shows narrowing of the gyri and a widening of the sulci.
Histologic changes
Most prominent in the cortex
Neuritic (senile) plaques
Neurofibrillary tangles
Granulovacuolar degeneration
Deposition of amyloid in the neuritic plaques and the wall of the cerebral vessels |
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Term
|
Definition
Subcortical neurodegenerative disorder
Typically affects elderly persons
Cause unknown
Decreased number of dopaminergic neurons in the substantia nigra
Disturbances of movement, primarily tumor, rigidity, bradykinesia, postural instability |
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Term
|
Definition
Tremor or twitching of the muscles
Instability while walking
Depression and dementia
Significant number of patients become depressed, and about 10% develop dementia.
Gross examination
Substantia nigra appears pale.
Histologically
Loss of melanin-rich neurons
Lewy bodies |
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Term
|
Definition
Autosomal dominant neurodegenerative disease
Involuntary, gyrating movements and progressive dementia
Atrophy of the cortex and subcortical nuclei, most prominently the caudate and putamen |
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Term
|
Definition
Nonspecific histologic changes include:
Atrophy, degeneration, loss of neurons, reactive gliosis
First symptoms usually do not appear before midlife.
Most affected patients become mentally incapacitated by the age of 50 to 60 years. |
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Term
| Amyotrophic Lateral Sclerosis |
|
Definition
Neurodegenerative disease
Affects older men and women
Motor weakness and progressive wasting of muscles in the extremities (small hand muscles)
Fasciculations (involuntary twitching)
Slurred speech but the intellect is not affected |
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Term
| Amyotrophic Lateral Sclerosis |
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Definition
Loss of motor neurons in the spinal cord, midbrain, and cerebral cortex
Loss of the lateral cerebrospinal pathways in the spinal cord
Incurable, progressive disease that leads to death over a period of a few years |
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Term
|
Definition
Most common CNS tumor
Peak incidence—65 years
Lateral hemispheres
Gross appearance
Parts of the tumor are necrotic and yellow
Parts are hemorrhagic red, and parts are white
Irregularly shaped
Poorly demarcated
Butterfly-like appearance |
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Term
|
Definition
Histologically
Highly anaplastic astrocytic cells
Cell appearance—may retain a fetal appearance or become enlarged, bizarre shaped, or multinucleated with well-developed cytoplasm
Numerous mitotic figures
Proliferative changes of blood vessels |
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Term
|
Definition
Of all brain tumors, 50% represent metastases.
They may be solitary or multiple.
Most common tumors metastasizing to the brain are:
Lung cancer
Breast cancer
Melanoma |
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Term
| Diseases of the Middle Ear |
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Definition
Acute otitis media—infectious or noninfectious
Otitis media is a common disease characterized by acute or chronic suppurative inflammation of the middle ear.
Common causes are Streptococcus pyogenes and the pneumococcus.
The middle ear is usually infected by pharyngeal organisms that reach the middle ear via the auditory tube.
It usually occurs in children as a complication of viral and bacterial infections of the pharynx |
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Term
|
Definition
the middle ear is filled with purulent exudate.
The reddened tympanic membrane bulges into the external auditory meatus and may rupture, leading to a purulent discharge from the ear
In acute otitis media there is earache and fever.
The diagnosis is made by noting the outward-bulging, tense, reddened tympanic membrane.
In cases where the membrane has ruptured, there is a purulent discharge from the ear. Impairment of hearing is common in these cases.
Culture of the exudate is necessary to identify the causative bacterium |
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Term
|
Definition
Clinically presents as a triad:
Episodic vertigo, one to several hours
Sensory hearing loss for low-frequency sounds
Tinnitus, or ringing in the ears
Pathogenesis—increased endolymphatic pressure resulting from unknown causes
Clinically, Meniere's disease is characterized by fluctuating hearing loss and tinnitus, episodic vertigo, and a sensation of fullness in the ear.
After several years, permanent and progressive hearing loss develops.
No effective treatment is available.
Treatment with diuretics is of value in some patients; otherwise, surgery may be used in an attempt to relieve the pressure |
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Term
|
Definition
Deafness, or hearing loss, is very common, affecting at least 28 million Americans.
Deafness is classified as:
Conductive—external or middle ear lesions (e.g., loss of tympanic membrane)
Sensory—cochlear abnormalities
Neural—lesions of cranial nerve VIII or CNS |
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Term
|
Definition
chlamydial infection in which there is long-term destruction of the cornea, leading to blindness in cases that are not treated early.
The acute conjunctival inflammation progresses to a chronic phase in which there may be epithelial hyperplasia, lymphocytic infiltration, and pannus formation—the last an inflamed mass of granulation tissue that replaces the superficial layers of the cornea and results in blindness.
Trachoma is the most common cause of blindness in underdeveloped tropical countries |
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Term
|
Definition
Narrow, irregular arteries with thickened walls characterize mild to moderate hypertension.
Malignant hypertension leads to
papilledema,
retinal hemorrhages,
and fluffy exudates (cotton wool spots)—ill-defined areas of edema and repair resulting from ischemia |
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Term
|
Definition
Diabetic retinopathy is classified into two stages: nonproliferative and proliferative.
Nonproliferative diabetic retinopathy usually appears late in the first decade or early in the second decade of the disease and is marked by retinal vascular microaneurysms, blot hemorrhages, and cotton wool spots
The appearance of neovascularization in response to retinal hypoxia is the hallmark of proliferative diabetic retinopathy.
These newly formed vessels appear near the optic nerve and/or macula and rupture easily, leading to vitreous hemorrhage, fibrosis, and ultimately retinal detachment |
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Term
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Definition
Senile cataract—the most common form of cataract, found in 60% of people older than 70 years; cause unknown
Secondary cataract—caused by identifiable events or diseases such as:
Trauma
Radiation
Inflammation
Diabetes |
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Term
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Definition
Opacification of the lens
Despite the fact that the oldest epithelial cells become compressed centrally throughout life, the lens normally remains transparent. Most individuals develop some lens opacification in later life (senile cataract).
Clinically, cataracts cause progressive loss of visual acuity. Halos or spots in the visual field are early symptoms.
Current treatment methods, which include extraction of the cataract and implantation of a prosthetic lens, are very successful |
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