Polycystic kidney in an adult Persian cat: clinical, diagnostic imaging, pathologic, and clinical pathologic evaluations

In the Persian cat, polycystic kidney disease is inherited as an autosomal dominant trait. Affected Persian cats usually do not develop chronic renal failure until later in adult life (3–10 years; average, 7 years). An affected 4.5-year-old male Persian cat referred with depression, lethargy, and anorexia that were present for 2 months before referring to us. Weight loss was one of the problems reported by the owner. In physical examination, pale mucus membranes, tachycardia, and stomatitis prevailed. Laboratory findings were compatible to that of chronic renal diseases. In ultrasonographic examination, right and left kidneys were 4.3 × 2 and 4.3 × 2.5 cm, respectively. Multiple renal cysts were seen in both kidneys. Cysts had thin walls with anechoic contents and strong distal echo enhancement. The cat died after 2 months probably due to uremia. Necropsy findings showed small locations of hemorrhage in the stomach. Sever Stomatitis was also noted. Necropsic examination of the kidneys showed several cysts in the cortex and medulla of both kidneys. Most of these cysts were filled with fluids. Microscopic examination showed many cysts of 800–8,000-μm diameters. Some cellular infiltrates were also seen in some regions. Interstitial connective tissues were developed around cysts.     

Polycystic disease of the kidney in related mink

Polycystic kidneys in young related mink kits were seen on a mink farm in 1983 (4 kits) and 1984 (6 kits). The kits showed retarded growth and locomotor abnormalities leading to death in the 1983 kits at the age of 4 months. The renal cysts involved the collecting tubules; there was vacuolization and focal hyperplasia of the epithelium. Other organs were normal. The data available for the condition in mink are insufficient as yet to explain the mode of inheritance.     

Polycystic disease of kidney, liver and pancreas; a possible patholgenesis.

5,6,7,8-tetrahydrocarbzzole-3-acetic acid (AH 2835) given to maternal rats throughout their gestation produces an experimental model of the autosomally inherited human infantile polycystic disease Potter type I in the rat foetuses. The affected animals have cystic lesions in their kidneys, liver and pancreas like those seen in the human. Evidence is presented for the aetiology of the experimental lesion being related to the action of AH 2835 on the specific activity of the ouabain sensitive (Na+ + K+)-ATPase of absorptive epithelia. It is noted that two cystic kidney diseases, the ocngenital nephrotic syndrome and infantile polycystic disease Potter type I are both inherited as autosomal recessive traits and are therefore likely to be caused by enzyme abnormalities, and that the compound AH 2835 can be used to produce experimental models of both of these diseases.     

Polycystic liver disease in golden hamsters

Seven cases of multiple hepatic cysts of varying sizes and shapes were recorded in a closed colony of golden hamsters. Ante-mortem examination failed to show any clinical signs except for abdominal enlargement in one hamster. Multiple, thin-walled cysts of varying sizes (0.25 to 3.0 cm) and shape were observed in the liver. The larger cysts protruded from the liver surfaces and contained a colourless, clear, serous fluid and caused pathological change in 5-60 per cent of the hepatic parenchyma. Microscopically, the cysts were uni- or multilocular and lined by low cuboidal or flattened epithelial cells. The hepatic parenchyma around cysts showed pressure atrophy, necrosis, engorged sinusoids or other blood vessels or even haemorrhages, mild to extensive fatty or vacuolar degenerative changes and occasionally proliferation of biliary ducts.     

Polycystic kidney disease in the CBA/N immunodeficient mouse.

We describe a polycystic lesion of the kidney in the CBA/N mouse with an X-linked recessive immunodeficient syndrome. There is progressive cystic dilatation affecting all parts of the nephron. The cyst lining is composed of a single layered epithelium with focal nuclear crowding and the formation of micropapillary structures. The cystic epithelial cells show subnuclear vacuolation. Focal basement membrane thickening is also a feature. There is no significant inflammatory infiltrate present within these kidneys. Electron microscopic examination reveals that the subnuclear vacuolation is due to loss of the membrane infoldings at the basal pole of the epithelial cell with fluid accumulation within the extracellular space. The basement membrane thickening is due to expansion of the lamina densa. These changes are not present at birth but develop progressively with age. The finding of a polycystic kidney lesion in these mice offers an opportunity to investigate the relationship between the immune system and renal cyst formation.     

Polycystic kidney disease: a predominance of giant nephrons

Polycystic kidney disease is a bilateral disorder that affects approximately 200,000-400,000 persons in the United States. The most common form of the disease is inherited as an autosomal dominant trait (ADPKD). It typically causes renal insufficiency by the fifth or sixth decade of life. The disease is characterized by the progressive enlargement of a portion of renal tubule segments (proximal, distal, loop of Henle, collecting duct). The tubules enlarge from a normal diameter of 40 microns to several centimeters in diameter, causing marked gross and microscopic anatomic distortion. The cause of the cystic change in the tubules is unknown, but current possibilities include obstruction of tubule fluid flow by hyperplastic tubule cells, increased compliance of the tubule basement membranes, and/or increased radial growth of cells in specific portions of the renal tubule. Several studies show that the epithelia of the cysts continue to transport Na+, K+, Cl-, H+, and organic cations and anions in a qualitative fashion similar to that of the tubule segment from which they were derived. ADPKD, then, is a disease in which some gigantic renal tubules, over a period of several decades, impair the function of nonaffected nephrons and thereby lead to renal failure.     

Exaggerated natriuresis in adult polycystic kidney disease

Angiotensin II (AII), aldosterone (Aldo) arginine vasopressin (AVP) in plasma, serum osmolality (Sosm), and renal sodium excretion (UNaV) were studied before and after infusion of hypertonic sodium chloride solution in 20 patients with adult polycystic kidney disease (PKD) with normal or moderately reduced creatinine clearance (Ccr) and in 10 healthy control subjects. UNaV increased after sodium loading in all, significantly more in the PKD patients. AII and Aldo were normal before sodium loading and suppressed after saline in PKD patients and controls. The increase in VNaV correlated with Aldo in patients but not in controls. AVP before loading was increased in hypertensive PKD patients with reduced Ccr, but not in normotensive patients with normal Ccr. After hypertonic saline, Sosm increased to the same degree both in PKD and control subjects, but AVP increased more in those with PKD. The exaggerated natriuresis of PKD is probably not explained by a change in the activity of the renin-angiotensin-aldosterone system. The enhanced response of AVP to osmotic stimuli in PKD may be a compensatory reaction to a reduced renal tubular effect of AVP.     

Genetic counseling in adult polycystic kidney disease

We evaluated 22 patients with end-stage renal disease (ESRD) due to adult polycystic kidney disease (APKD) to assess their knowledge of the hereditary nature of the condition and to determine whether they received adequate genetic counseling. Patients were evaluated by means of a questionnaire and a review of their medical records. Only 5 of 22 (23%) knew their disorder was hereditary at the time of diagnosis, and in only 4 (18%) was genetic counseling suggested. In no instance had proband and spouse received genetic counseling together. Diagnostic studies of children at risk were rarely suggested. We also evaluated the children of 9 probands for APKD. Of 26 children evaluated, 17 had APKD (65%). Sixteen had no children at the time of testing. All but two of the 26 were less than 25 years old. Of the probands' children over 15 years of age, 55% knew the name of the condition in the family but only 9% knew they should be tested. Our study demonstrated inadequacy of genetic counseling and follow-up in this group of patients; we suggest that referral for counseling become a routine part of their management. Early diagnosis and effective counseling has the potential benefit for the individuals of making rational reproductive decisions appropriate for their situation. Counseling may have to be repeated during the course of the patients' disease, as their perception of risk may change with time. With advances in dialysis and transplantation, ESRD may not be as devastating in years to come as it is now.     

Polycystic kidney disease in SBM transgenic mice: role of c-myc in disease induction and progression.

SBM mouse is a unique transgenic model of polycystic kidney disease (PKD) produced by dysregulation of c-myc in the kidneys. Our previous demonstration that c-myc is overexpressed in human autosomal polycystic kidney disease (ADPKD) prompted us to investigate the pathogenetic role of c-myc in the induction and progression of the cystogenic phenotype in our mouse model. In young SBM kidneys, c-myc was two- to threefold increased with persistent expression levels into adulthood, an age when c-myc is normally undetectable. In situ hybridization analysis of the c-myc transgene demonstrated intense signal specifically overlying glomerular and tubular epithelium of developing cysts in fetal and young kidneys. Increased expression of c-myc correlated with the initiation and progression of the PKD phenotype as evidenced by early tubular and glomerular cysts at E16.5. Cyst number and size increased with age, with co-development of glomerular and tubular epithelial hyperplasia. Consistently, the mean renal proliferative index was increased approximately 5- to 20-fold in noncystic and cystic tubules of newborn SBM animals compared with littermate controls. Similarly, in fetal and newborn kidneys the tubular apoptotic indices were increased approximately three- to ninefold over controls. Both proliferation and apoptotic rates in cystic tubules approached levels in developing tubules from the normal nephrogenic zone. We conclude that the pathogenesis of PKD hinges on a critical imbalance in c-myc regulation of the opposing processes of cell proliferation and apoptosis, recapitulating the cellular phenomena in developing fetal kidney.     

Primary pleomorphic rhabdomyosarcoma of the kidney in an adult

Sarcoma of the kidney is uncommon and represents between 1% and 3% of all malignant renal tumors. Primary rhabdomyosarcoma of the kidney in adult age is unusual, and only sporadic cases have been reported. This is a very aggressive tumor with dismal prognosis. We report a new case of pleomorphic rhabdomyosarcoma of the kidney in an adult patient.     

Polycystic kidney disease, biliary dysgenesis in a patient with Larsen's syndrome

Larsen's syndrome is characterised by multiple joint dislocations, flat face and talipes equinovarus. There is an autosomal dominant form and also a more severe autosomal recessive form. Several types of polycystic kidney disease have been reported in children. In this report we present an infant with a severe form of Larsen's syndrome (thought to be lethal Larsen-like), infantile-type polycystic kidney disease, biliary dysgenesis and osteosclerosis.     

Polycystic kidney disease in a patient with the oral-facial-digital syndrome - type I.

Bilateral polycystic kidneys and chronic renal failure were observed in a 48-year-old woman with the classic clinical features of the oral-facial-digital syndrome, Type I (OFD-I). Since this association has been previously reported in two other patients, these findings suggest that polycystic kidneys may be a hitherto unrecognized manifestation of the oral-facial-digital syndrome.     

Gemfibrozil absorption and elimination in kidney and liver disease

Summary The disposition of the lipid-lowering drug gemfibrozil was studied in patients with either renal (n= 8) or hepatic disease (n= 8) and compared to those of healthy volunteers (n= 6). Gemfibrozil was determined in plasma and urine by means of a HPLC method. Urine was also analyzed for gemfibrozil conjugates.Following oral administration of 900 mg gemfibrozil, maximal plasma levels of the parent drug were 46.1±15.8 g/ml, attained after 2.2±1.1 h. In chronic renal failure and in liver cirrhosis the plasma concentrations of gemfibrozil did not significantly differ from that of controls except in those patients who were comedicated with antacids. These patients had significantly lower C_max and AUC values. The elimination half-life of the drug was 1.5 h in controls, 2.4 h in renal failure, and 2.1 h in liver disease. In healthy volunteers, only 0.02 to 0.15% of the given dose was recovered in the urine as parent gemfibrozil, while conjugates made up 7–14%. In patients with renal failure also, only traces of parent gemfibrozil could be detected, and conjugates accounted for 0.5–9.8%. In those with liver disease, however, about 0.1–0.2% were recovered in urine as parent gemfibrozil and up to 50% as conjugates. Strikingly, the amount of excreted conjugates in the urine was positively correlated to the direct bilirubin plasma concentration. It can be concluded that the elimination of gemfibrozil is not significantly influenced by renal failure. However, comedication with antacids markedly reduced plasma disposition of the drug. Patients with severe liver disease excreted more conjugated gemfibrozil via the kidney than did healthy controls. Thus, transfer across the canalicular cell membrane to the bile duct, rather than drug metabolization, is primarily disturbed in liver disease. Gemfibrozil accumulation is unlikely to occur in either kidney or liver disease.Abbreviations Cl_r creatinine clearance (ml/min) - HPLC high pressure liquid chromatography - C_max maximal plasma concentration (g/ml) - t_max time (h) after which C_max is attained - k_e elimination rate constant (h^–1) - t_1/2 elimination half-life (h) - A_e amount of drug excreted into the urine (% of given dose) - MRT mean residence time (h) - AUMC area under the first moment curve (g h²/ml) - AUC area under the plasma level time curve (g·h/ml) - ANOVA analysis of variance The paper is gratefully dedicated to G.W. Löhr