Sunday, 9 October 2011
Cylindrical dilatation of renal tubules is seen in -
a)Polycystic disease ‘of kidney(Jipmer 95)
b)Medullary cystic disease
c)Wilms tumour
d)Lipoid nephrosis
a)Polycystic disease ‘of kidney(Jipmer 95)
b)Medullary cystic disease
c)Wilms tumour
d)Lipoid nephrosis
Ans. is ‘a’ i.e., Polycystic disease of kidney [Ref : Robbin's 7h/e p. 966 & 6ep. 940, see morphology 9th line]
AUTOSOMAL RECESSIVE (CHILDHOOD) POLYCYSTIC KIDNEY DISEASE
This rare developmental anomaly is genetically distinct from adult polycystic kidney disease, having an autosomal recessive type of inheritance. Perinatal, neonatal, infantile, and juvenile subcategories have been defined, depending on time of presentation and presence of associated hepatic lesions. The first two are most common; serious manifestations are usually present at birth, and the young infant may succumb rapidly to renal failure.
MORPHOLOGY.
Kidneys are enlarged and have a smooth external appearance. On cut section, numerous small cysts in the cortex and medulla give the kidney a spongelike appearance. Dilated elongated channels are present at right angles to the cortical surface, completely replacing the medulla and cortex (Fig. 21-8 C). On microscopic examination, there is saccular or, more commonly, cylindrical dilation of all collecting tubules. The cysts have a uniform lining of cuboidal cells, reflecting their origin from the collecting tubules. The disease is invariably bilateral. In almost all cases, there are multiple epithelium-lined cysts in the liver (Fig. 21-8 D) as well as proliferation of portal bile ducts.
Patients who survive infancy (infantile and juvenile form) may develop a peculiar type of hepatic fibrosis characterized by bland periportal fibrosis and proliferation of well-differentiated biliary ductules, a condition now termed congenital hepatic fibrosis. In older children, the hepatic picture in fact predominates. Such patients may develop portal hypertension with splenomegaly. Curiously, congenital hepatic fibrosis sometimes occurs in the absence of polycystic kidneys and has been reported occasionally in the presence of adult polycystic kidney disease.
This rare developmental anomaly is genetically distinct from adult polycystic kidney disease, having an autosomal recessive type of inheritance. Perinatal, neonatal, infantile, and juvenile subcategories have been defined, depending on time of presentation and presence of associated hepatic lesions. The first two are most common; serious manifestations are usually present at birth, and the young infant may succumb rapidly to renal failure.
MORPHOLOGY.
Kidneys are enlarged and have a smooth external appearance. On cut section, numerous small cysts in the cortex and medulla give the kidney a spongelike appearance. Dilated elongated channels are present at right angles to the cortical surface, completely replacing the medulla and cortex (Fig. 21-8 C). On microscopic examination, there is saccular or, more commonly, cylindrical dilation of all collecting tubules. The cysts have a uniform lining of cuboidal cells, reflecting their origin from the collecting tubules. The disease is invariably bilateral. In almost all cases, there are multiple epithelium-lined cysts in the liver (Fig. 21-8 D) as well as proliferation of portal bile ducts.
Patients who survive infancy (infantile and juvenile form) may develop a peculiar type of hepatic fibrosis characterized by bland periportal fibrosis and proliferation of well-differentiated biliary ductules, a condition now termed congenital hepatic fibrosis. In older children, the hepatic picture in fact predominates. Such patients may develop portal hypertension with splenomegaly. Curiously, congenital hepatic fibrosis sometimes occurs in the absence of polycystic kidneys and has been reported occasionally in the presence of adult polycystic kidney disease.
FOR THE ABOVE QUESTION:-At birth the kidneys are enlarged with a smooth external surface. The distal tubules and collecting ducts are dilated into elongated cysts that are arranged in a radial fashion. As the patient ages, the cysts may become more spherical and the disease can be confused withADPKD. Interstitial fibrosis is also seen as renal function deteriorates. Liver involvement includes proliferation and dilation of small intrahepatic bile ducts as well as periportal fibrosis.
FROM HARRISON 15TH ED 1600(ITS NOT THERE IN 17TH ED)
Sunday, 9 October 2011 1
Bilateral contracted kidney occurs in all except
a)Diabetes mellitus (AIIMS 90)
b)Benign nephrosclerosis
c)Chronic pyelonephritis
d)Chronic glomerular nephritis
a)Diabetes mellitus (AIIMS 90)
b)Benign nephrosclerosis
c)Chronic pyelonephritis
d)Chronic glomerular nephritis
Ans. is ‘a’ i.e., Diabetes mellitus [Ref : Chandrasoma taylor 3rd/e p. 725, table (49.2)]
Table 49–2. Differential Diagnosis of a Granular, Contracted Kidney.
ARE :-Chronic Glomerulonephritis Chronic Pyelonephritis Benign Nephrosclerosis (Hypertension)
Antiglomerular antibodies are present in —
a)Good pasture syndrome (Al 90)
b)Focal gloumerulonephritis
c)Membramcous glomerulonephritis
d)Membrano proliferative glomerulonephritis
a)Good pasture syndrome (Al 90)
b)Focal gloumerulonephritis
c)Membramcous glomerulonephritis
d)Membrano proliferative glomerulonephritis
RPGN may be caused by a number of different diseases, some restricted to the kidney and others systemic. [34] Although no single mechanism can explain all cases, there is little doubt that in most cases the glomerular injury is immunologically mediated. Thus, a practical classification divides RPGN into three groups on the basis of immunologic findings (Table 21-6) . In each group, the disease may be associated with a known disorder or it may be idiopathic.
Type I RPGN is best remembered as anti-GBM disease and hence is characterized by linear deposits of IgG and, in many cases, C3 in the GBM, as previously described. In some of these patients, the anti-GBM antibodies cross-react with pulmonary alveolar basement membranes to produce
TABLE 21-6 — RAPIDLY PROGRESSIVE GLOMERULONEPHRITIS (RPGN)
TYPE 1 RPGN
Idiopathic
Goodpasture syndrome
TYPE II RPGN (immune complex)
Idiopathic
Postinfectious
Systemic lupus erythematosus
Henoch-Schonlein purpura (IgA)
Others
TYPE III RPGN (pauci-immune)
(ANCA associated)
Idiopathic
Wegener granulomatosis
Microscopic polyarteritis nodosa
the clinical picture of pulmonary hemorrhages associated with renal failure ( Goodpasture syndrome). The Goodpasture antigen, as noted, resides in the noncollagenous portion of the alpha3 chain of collagen type IV. What triggers the formation of these antibodies is unclear in most patients. Exposure to viruses or hydrocarbon solvents (found in paints and dyes) has been implicated in some patients, as have various drugs and cancers. Cigarette smoking appears to play a permissive role, since most patients who develop pulmonary hemorrhage are smokers. There is a high prevalence of certain HLA subtypes and haplotypes (e.g., HLA-DRB1), a finding consistent with the genetic predisposition to autoimmunity. [34]
Type II RPGN is an immune complex- mediated disease. It can be a complication of any of the immune complex nephritides, including postinfectious glomerulonephritis, SLE, IgA nephropathy, and Henoch-Schonlein purpura. In some cases, immune complexes can be demonstrated, but the underlying cause is undetermined. In all of these cases, immunofluorescence studies reveal the characteristic (“lumpy bumpy”) granular pattern of staining. These patients cannot usually be helped by plasmapheresis, and they require treatment for the underlying disease.
Type III RPGN, also called pauci-immune type, is defined by the lack of anti-GBM antibodies or immune complexes by immunofluorescence and electron microscopy. Most of these patients have antineutrophil cytoplasmic antibody (ANCA) in the serum, which, as we have seen (Chapter 12) , plays a role in some vasculitides. Hence, in some cases, type III RPGN is a component of a systemic vasculitis such as Wegener granulomatosis or microscopic polyarteritis. In many cases, however, pauci-immune crescentic glomerulonephritis is isolated and hence idiopathic. More than 90% of such idiopathic cases have C-ANCA or P-ANCA in the sera.
To summarize, all three types of RPGN may be associated with a well-defined renal or extrarenal disease, but in many cases (approximately 50%) the disorder is idiopathic. Of the idiopathic cases, about one fourth have anti-GBM disease (RPGN type I) without lung involvement; another one fourth have type II RPGN; and the remainder are pauci-immune or type III RPGN. The common denominator in all types of RPGN is severe glomerular injury.
In crescentric glomerulonephritis, prognosis depends on —(AI 90)
a) Size
b) Cellularity
c) Number
d) Basement membrane break
Ans. is ‘c’ i.e., Number [Ref : Basic Robbin's p. 453]
A crescent is a half-moon-shaped collection of cells in Bowman’s space, usually composed of proliferating parietal epithelial cells and infiltrating monocytes. Because crescentic glomerulonephritis is often associated with renal failure that progresses rapidly over week to months, the clinical term rapidly progressive glomerulonephritis and pathologic term crescentic glomerulonephritis are often used interchangeably
a) Size
b) Cellularity
c) Number
d) Basement membrane break
Ans. is ‘c’ i.e., Number [Ref : Basic Robbin's p. 453]
A crescent is a half-moon-shaped collection of cells in Bowman’s space, usually composed of proliferating parietal epithelial cells and infiltrating monocytes. Because crescentic glomerulonephritis is often associated with renal failure that progresses rapidly over week to months, the clinical term rapidly progressive glomerulonephritis and pathologic term crescentic glomerulonephritis are often used interchangeably
Transitional cell carcinomas can be caused by —
a) Napthylamine
b) Smoking
c) Bilharziasis
d) Betel nut
Ans. Three options are correct i.e., ‘a, b & c’ {Ref : Robbin’s 7″/e p. 1029 & 6th/e p. 1007]
A number of factors have been implicated in the causation of transitional cell carcinoma. Some of the more important contributors include the following:
Cigarette smoking is clearly the most important influence, increasing the risk threefold to sevenfold, depending on the pack-years and smoking habits. Fifty per cent to 80% of all bladder cancers among men are associated with the use of cigarettes. Cigars, pipes, and smokeless tobacco invoke a much smaller risk.
Industrial exposure to arylamines, particularly 2-naphthylamine as well as related compounds, as pointed out in the earlier discussion of chemical carcinogenesis (Chapter
. The cancers appear 15 to 40 years after the first exposure.
Schistosoma haematobium infections in areas where these are endemic (Egypt, Sudan) are an established risk. The ova are deposited in the bladder wall and incite a brisk chronic inflammatory response that induces progressive mucosal squamous metaplasia and dysplasia and, in some instances, neoplasia. Seventy per cent of the cancers are squamous, the remainder being transitional cell carcinoma.
Long-term use of analgesics, implicated also in analgesic nephropathy (Chapter 21) .
Heavy long-term exposure to cyclophosphamide, an immunosuppressive agent, induces as noted hemorrhagic cystitis and increases the risk of bladder cancer.
How these influences induce cancer is unclear, but a number of genetic alterations have been observed in transitional cell carcinoma. The cytogenetic and molecular alterations are heterogeneous. Particularly common (occurring in 30% to 60% of tumors studied) are chromosome 9 monosomy or deletions of 9p and 9q as well as deletions of 17p, 13q, 11p, and 14q. [8] The chromosome 9 deletions are the only genetic changes present frequently in superficial papillary tumors and occasionally in noninvasive flat tumors.
a) Napthylamine
b) Smoking
c) Bilharziasis
d) Betel nut
Ans. Three options are correct i.e., ‘a, b & c’ {Ref : Robbin’s 7″/e p. 1029 & 6th/e p. 1007]
A number of factors have been implicated in the causation of transitional cell carcinoma. Some of the more important contributors include the following:
Cigarette smoking is clearly the most important influence, increasing the risk threefold to sevenfold, depending on the pack-years and smoking habits. Fifty per cent to 80% of all bladder cancers among men are associated with the use of cigarettes. Cigars, pipes, and smokeless tobacco invoke a much smaller risk.
Industrial exposure to arylamines, particularly 2-naphthylamine as well as related compounds, as pointed out in the earlier discussion of chemical carcinogenesis (Chapter
. The cancers appear 15 to 40 years after the first exposure. Schistosoma haematobium infections in areas where these are endemic (Egypt, Sudan) are an established risk. The ova are deposited in the bladder wall and incite a brisk chronic inflammatory response that induces progressive mucosal squamous metaplasia and dysplasia and, in some instances, neoplasia. Seventy per cent of the cancers are squamous, the remainder being transitional cell carcinoma.
Long-term use of analgesics, implicated also in analgesic nephropathy (Chapter 21) .
Heavy long-term exposure to cyclophosphamide, an immunosuppressive agent, induces as noted hemorrhagic cystitis and increases the risk of bladder cancer.
How these influences induce cancer is unclear, but a number of genetic alterations have been observed in transitional cell carcinoma. The cytogenetic and molecular alterations are heterogeneous. Particularly common (occurring in 30% to 60% of tumors studied) are chromosome 9 monosomy or deletions of 9p and 9q as well as deletions of 17p, 13q, 11p, and 14q. [8] The chromosome 9 deletions are the only genetic changes present frequently in superficial papillary tumors and occasionally in noninvasive flat tumors.
IMPORTANT POINT IN TREATMENT OF TRANSITIONAL CELL CARCINOMA OF BLADDER:–Intravesical therapies are used in two general contexts: as an adjuvant to
a complete endoscopic resection to prevent recurrence or, less commonly,
to eliminate disease that cannot be controlled by endoscopic resection
alone. Intravesical treatments are advised for patients with recurrent disease,
>40% involvement of the bladder surface by tumor, diffuse CIS, or T1
disease. The standard intravesical therapy, based on randomized comparisons,
is bacillus Calmette-Guerin (BCG) in six weekly instillations, followed
by monthly maintenance administrations for ≥1 year
a complete endoscopic resection to prevent recurrence or, less commonly,
to eliminate disease that cannot be controlled by endoscopic resection
alone. Intravesical treatments are advised for patients with recurrent disease,
>40% involvement of the bladder surface by tumor, diffuse CIS, or T1
disease. The standard intravesical therapy, based on randomized comparisons,
is bacillus Calmette-Guerin (BCG) in six weekly instillations, followed
by monthly maintenance administrations for ≥1 year
At least 95% of cancers of the oral cavity (including the tongue) are squamous cell carcinomas.A major regional predisposing influence is the chewing of betel nuts and pan in India and parts of Asia.
SO BETEL NUT IS RELATED TO SQUAMOUS CELL CARCINOMA NOT TRANSITIONAL CELL.
Though smoking is related to both types.
SO BETEL NUT IS RELATED TO SQUAMOUS CELL CARCINOMA NOT TRANSITIONAL CELL.
Though smoking is related to both types.
The intracytoplasmic vacuoles seen in the Armmani Epstein cell are rich in -
a) Na and K’
b) Glycogen
c) Lipids
d) None of the above
a) Na and K’
b) Glycogen
c) Lipids
d) None of the above
ans is B
Glycogen vacuolation of the terminal part of the proxcimal convoluted tubules (loops of Henle) in diabetic patients, directly related to hyperglycemia and glycosuria..Tuesday, 4 October 2011
Assuming the subject in the preceding question is a normal adult, we can conclude that most likely potassium is
A. filtered but not secreted or reabsorbed
B. secreted but not filtered or reabsorbed
C. reabsorbed but not secreted or filtered
D. filtered and secreted
E. filtered and reabsorbed
E. Since CK is less than GFR (80 ml/min, as measured by creatinine clearance in question 12), potassium must be filtered and reabsorbed.
Tuesday, 4 October 2011 0
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