Adult dominant polycystic kidney disease--clinical problems

Colonic diverticular disease in autosomal dominant polycystic kidney disease: is there really an association? A nationwide analysis

PURPOSE

Colonic diverticulosis, diverticulitis, and diverticular bleeding are reportedly more common in patients with autosomal dominant polycystic kidney disease (ADPKD). Other studies have questioned this association. The objectives of our study are to clarify this association using a larger patient population and to identify risk factors in general to develop diverticular disease.

METHODS

The Nationwide Inpatient Sample weighted discharges from 2003 to 2011 were used to assess for the prevalence of diverticular disease in the population with ADPKD compared with the general population without ADPKD. A multivariable direct logistic regression model was constructed to determine independent predictors of diverticular disease in the general population.

RESULTS

The prevalence of diverticulosis, diverticulitis, and diverticular bleeding were considerably increased in patients with ADPKD compared with the general population without ADPKD. The prevalence of colonic surgery was less in ADPKD patients with diverticulitis. In patients with kidney transplant, the prevalence of diverticulitis was increased in the ADPKD group, but colonic surgery was not significantly different between both groups. The prevalence of diverticular bleeding was slightly elevated in patients with ADPKD, but colonic surgery was significantly increased in patients with ADPKD. NSAID use, hypertension, constipation, and ADPKD had increased odds ratios for diverticular disease during multivariate analysis.

CONCLUSION

There is an increased prevalence of colonic diverticular disease in the population with ADPKD.

Epidemiology of Autosomal Dominant Polycystic Kidney Disease in Olmsted County

BACKGROUND AND OBJECTIVES

The prevalence of autosomal dominant polycystic kidney disease (ADPKD) remains controversial. Incidence rates in Olmsted County, Minnesota, during 1935-1980 were previously reported. The current work extends this study to 2016.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Rochester Epidemiology Project and radiology databases of Mayo Clinic and Olmsted Medical Center (healthcare providers for Olmsted County) were searched to identify all subjects meeting diagnostic criteria for definite, likely, and possible ADPKD. Annual incidence rates were calculated using incident cases during 1980-2016 as numerator and age- and sex-specific estimates of the population of Olmsted County as denominator. Point prevalence was calculated using prevalence cases as numerator and age- and sex-specific estimates of the population of Olmsted County on January 1, 2010 as denominator. Survival curves from the time of diagnosis were compared with expected survival of the Minnesota population.

RESULTS

The age- and sex-adjusted annual incidence of definite and likely ADPKD diagnosis during 1980-2016 was 3.06 (95% CI, 2.52 to 3.60) per 100,000 person-years, which is 2.2 times higher than that previously reported for 1935-1980 (1.38 per 100,000 person-years). The point prevalence of definite or likely ADPKD on January 1, 2010 was 68 (95% CI, 53.90 to 82.13) per 100,000 population. Much higher incidence rates and point prevalence were obtained when possible ADPKD cases were included. Contrary to the previous Olmsted County study, patient survival in this study was not different from that in the general population.

CONCLUSIONS

The point prevalence of definite and likely ADPKD observed in this study is higher than those reported in the literature, but lower than genetic prevalence based on estimates of disease expectancy or on analysis of large population-sequencing databases.

Prevalence, risk factors and disease knowledge of polycystic kidney disease in Pakistan

Polycystic kidneys disease refers to cyst(s) formation in kidneys with severe consequences of end stage renal disease thus have higher mortality. It is a common genetic disease occurring either as autosomal dominant polycystic kidney (ADPKD) or autosomal recessive polycystic kidney disease (ARPKD) with prevalence rates of 1/1000 and 1/40,000 respectively. Dominant forms presenting in later (>30) while recessive in earlier ages (infancy) and affecting both sexes and almost all race. The patient experiences many renal as well as extra-renal manifestations with marked hypertension and cyst formation in other organs predominantly in liver. Due to genetic basis, positive family history is considered as major risk factor. Ultrasonography remains the main stay of diagnosis along with family history, by indicating increased renal size and architectural modifications. Initially disease remains asymptomatic, later on symptomatic treatment is suggested with surgical interventions like cyst decortications or drainage. Dialysis proved to be beneficial in end stage renal disease. However renal transplantation is the treatment of choice.

Clinical presentation and outcome of autosomal dominant polycystic kidney disease in Nigeria

INTRODUCTION

Autosomal Dominant Polycystic Kidney Disease (ADPKD) is presumably rare in Africa. Knowledge about the disease in Nigeria is limited as demonstrated by scanty articles on the subject.

OBJECTIVES

To determine the pattern of clinical presentation and outcome of ADPKD among ADPKD patients.

METHOD

ADPKD subjects were prospectively studied between January 1996 and December 2010. Their demographics, clinical and investigation parameters were documented. Dependency on dialysis, renal transplant and death were the final outcomes.

RESULTS

Forty one patients (M:F=1.3:1) with mean age of 48.6±4.6 years were studied. ADPKD was diagnosed at 2.73 cases per annum. Family history of ADPKD and hypertension were present in 56.1% and 82.9% respectively. Their mean systolic and diastolic blood pressures were 166.9 ±23.6 and 104 ±21.2 respectively.Nocturia (78.0%) and loin pain (68.3%) were the most common presenting symptoms. Liver cysts (31.7%) and aortic regurgitation (22.0%) were the predominant extra-renal manifestations.Twenty three (56.1%) received haemodialysis; no renal transplantation. Death rate was 51.2%. Presence of uraemia and intra-cerebral aneurysm contributed significantly to mortality.

CONCLUSION

ADPKD may not be so rare in Nigeria. Awareness campaign to change attitude of family members to screening and further studies using newer criteria for diagnosis of ADPKD should be conducted.

Severity of diverticulitis in patients with polycystic kidney disease without transplantation

BACKGROUND

Patients with polycystic kidney disease (PKD) who have had a kidney transplant have an increased risk of diverticular disease and complicated diverticulitis. Literature is limited regarding the severity of diverticulitis in patients with PKD who have not had a transplant. We aim to assess whether patients with PKD, with and without renal transplant, have a similar course of diverticulitis.

METHODS

A retrospective review of all adult PKD patients at our institution diagnosed with diverticulitis between 2000 and 2016 was conducted. Patients without documented PKD and diverticulitis were excluded. We compared PKD patients with and without renal transplantation.

RESULTS

A total of 41 patients were identified. Mean age was 60 (± 12), and 56% were female. Fourteen patients had undergone renal transplantation. Five (19%) non-transplant patients had complicated diverticulitis, compared to 43% (n = 6) transplanted (p = 0.33). Fifteen (56%) non-transplant and 8 (57%) transplant patients had recurrent diverticulitis (p = 1.00). Three (11%) non-transplant and 5 (36%) transplanted patients had recurrent complicated diverticulitis. Eight (30%) non-transplant and 7 (50%) transplant patients underwent surgery (p = 0.31). All 8 non-transplant patients underwent sigmoid resection with primary anastomosis without diversion. In the transplant group, 3 Hartmann procedures and 1 sigmoid resection with and 3 without diversion were performed. There was one in-hospital death in each group.

CONCLUSION

In our group of patients, there was no difference in rate of recurrent diverticulitis, diverticulitis complications, or operative intervention in patients with PKD with and without renal transplant. The renal transplant group had a higher rate of recurrent, complicated diverticulitis.

Percutaneous radiofrequency ablation with contrast-enhanced ultrasonography for solitary and sporadic renal cell carcinoma in patients with autosomal dominant polycystic kidney disease

Background

The aim of this study was to assess the functional and oncologic outcomes of percutaneous radiofrequency ablation (RFA) with contrast-enhanced ultrasonography (CEUS) for renal cell carcinoma in patient with autosomal dominant polycystic kidney.

Methods

We performed a retrospective review of five patients with renal cell carcinoma (RCC) in autosomal dominant polycystic kidney disease (ADPKD) from January 2009 to December 2014 with a media follow-up of 33 months. The tumors were ablated with Cool-tip RFA system under the guidance of CEUS. Routine follow-up included contrast-enhanced computed tomography/magnetic resonance imaging (CT/MRI) and renal function tests.

Results

Media diameter of the treated renal tumors was 3.1 cm (range 1.7–5.2 cm). Initial ablation success rate was 4/5. After over 6 months contrast-enhanced CT/MRI follow-up after RFA, no patients experienced local tumor recurrence. No patients required dialysis in the periprocedural period. Minor complications only developed in two cases. There was no significant difference in estimated glomerular filtration rate (eGFR) between pre- and post-RFA.

Conclusions

Our initial experience of this technique for RCC in ADPKD was favorable with good renal function preservation and oncologic outcomes. It may be a good choice for RCC in ADPKD.

Nephrotic syndrome and autosomal dominant polycystic kidney disease

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) is an inherited disorder characterized by the development and growth of cysts in the kidneys and other organs. In ADPKD patients, nephrotic range proteinuria is unusual and needs to be investigated further to exclude coexisting glomerular disease. Among the anecdotal case reports of ADPKD associated with nephrotic syndrome, focal segmental glomerulosclerosis occurs most frequently.

METHODS

We report the case of a 26-year-old male with ADPKD and concomitant nephrotic syndrome, in which an ultrasound (US)-guided renal biopsy showed a mesangioproliferative glomerulonephritis. We treated the patient with prednisone 1 mg/kg/day, because of the failure of treatment with angiotensin-converting enzyme inhibitor/angiotensin receptor blocker association.

RESULTS

After 6 months of steroid treatment, we observed a stability of his GFR and a reduction of proteinuria.

CONCLUSION

This case report and other cases of the literature underline the importance of a renal biopsy in patients with ADPKD and nephrotic syndrome in order to make an accurate diagnosis and an appropriate treatment/prevention of renal function deterioration.

Prevalence of cardiovascular events in patients with autosomal dominant polycystic kidney disease

BACKGROUND

This study evaluates the prevalence of cardiovascular events in autosomal dominant polycystic kidney disease (ADPKD) patients.

METHODS

We distributed surveys to 1,439 subjects from our ADPKD research database. In total, 426 subjects completed and returned surveys; 7 of these were from children and were excluded from the study.

RESULTS

The patients who responded were female (63.2%), nonHispanic (88.1%) and white (93.6%). The mean age of the total group was 53.2 ± 13.7 years; 82.8% had a family history of ADPKD and 32.5% had reached end-stage renal disease (ESRD). With respect to cardiovascular risk factors, 86.6% were hypertensive with a mean age at diagnosis of 36.9 ± 12.9 years and hypertension was significantly more prevalent in males. In addition, 19.6% of the subjects were obese, 20.8% were smokers, 8.7% had diabetes, 45.7% had high cholesterol and 17.8% were sedentary. The most prevalent self-reported cardiovascular events were arrhythmias (25.9%), evidence of peripheral vascular disease (16.5%), heart valve problems (14.4%), cardiac enlargement (9.5%), stroke or cerebral bleeding (7.5%), myocardial infarction (6%) and brain aneurysm (5.0%). The most commonly used antihypertensive medications were renin-angiotensin inhibitors used by 75% of ADPKD patients. Older ADPKD patients and those at ESRD had a significantly higher incidence of cardiovascular events.

CONCLUSION

These findings support the high prevalence of cardiovascular risk factors and events in ADPKD patients which contribute to a greater mortality risk. Due to the prevalence of cardiovascular risk factors in the ADPKD population, early diagnosis and clinical intervention are recommended.

Autosomal dominant polycystic kidney disease with diffuse proliferative glomerulonephritis - an unusual association: a case report and review of the literature

Introduction

Autosomal dominant polycystic kidney disease is an inherited disorder that is characterized by the development and growth of cysts in the kidneys and other organs. Urinary protein excretion is usually less than 1 g/24 hours in autosomal dominant polycystic kidney disease, and an association of nephrotic syndrome with this condition is considered rare. There are only anecdotal case reports of autosomal dominant polycystic kidney disease associated with nephrotic syndrome, with focal segmental glomerulosclerosis being the most commonly reported histopathological diagnosis. Nephrotic-range proteinuria in the presence of autosomal dominant polycystic kidney disease, with or without an accompanying decline in renal function, should be investigated by open renal biopsy to exclude coexisting glomerular disease. To the best of our knowledge, this is the first case of autosomal dominant polycystic kidney disease with histologically proven diffuse proliferative glomerulonephritis presenting with nephrotic-range proteinuria. No other reports of this could be found in a global electronic search of the literature.

Case presentation

We report the case of a 35-year-old Indo-Aryan man with autosomal dominant polycystic kidney disease associated with nephrotic syndrome and a concomitant decline in his glomerular filtration rate. Open renal biopsy revealed diffuse proliferative glomerulonephritis. An accurate diagnosis enabled us to manage him conservatively with a successful outcome, without the use of corticosteroid which is the standard treatment and the drug most commonly used to treat nephrotic syndrome empirically.

Conclusion

Despite the reluctance of physicians to carry out a renal biopsy on patients with autosomal dominant polycystic kidney disease, our case supports the idea that renal biopsy is needed in patients with polycystic kidney disease with nephrotic-range proteinuria to make an accurate diagnosis. It also illustrates the importance of open renal biopsy in planning appropriate treatment for patients with autosomal dominant polycystic kidney disease with nephrotic-range proteinuria. The treatment for various histological subtypes leading to nephrotic syndrome is different, and in this modern era we should practice evidence-based medicine and should avoid empirical therapy with its associated adverse effects.

Prevalence of renal cell carcinoma in patients with autosomal dominant polycystic kidney disease and chronic renal failure

OBJECTIVES

To study the prevalence and the characteristics of renal cell carcinoma (RCC) in patients with autosomal dominant polycystic kidney disease (ADPKD) in our series.

METHODS

We reviewed retrospectively all the nephrectomies performed in our department between 1982 and 2003 in patients with ADPKD and chronic renal failure.

RESULTS

Seventy-nine patients (42 males and 37 females) with ADPKD and chronic renal failure underwent 89 nephrectomies; in 10 of 79, both kidneys were removed but not simultaneously. Mean age was 50.4 years (range, 32-69 years). Of 79 patients, 50 had end-stage renal disease (ESRD) and were on hemodialysis or had received a transplant for >1 year. On histologic examination, 11 of 89 kidneys were diagnosed with carcinomas. There was 1 patient with bilateral tumor (tubulopapillary Ca) and 3 kidneys (27.3%) with multifocal tumors. Regarding the histologic type, there were 7 of 12 (58.3%) clear cell carcinomas and the remaining 5 (41.7%) were tubulopapillary carcinomas.

CONCLUSIONS

The prevalence of RCC was higher in patients with ADPKD and ESRD, with >1 year on dialysis or renal transplantation undergoing nephrectomy according the protocol. It would be 2 to 3 times more frequent than RCC in patients with ESRD alone. The clinician should maintain a high alert of suspicion for RCC in such patients.

Bilateral renal cell carcinoma in a patient with autosomal dominant polycystic kidney disease

Renal cell carcinoma (RCC) in autosomal dominant polycystic kidney disease (ADPKD) is very rare. Only 11 cases of bilateral RCC in ADPKD have been reported since 1954. Herein, we present a 58-year-old male who received laparoscopic bilateral radical nephrectomy for bilateral RCC with different cell variants in ADPKD and end-stage renal disease under regular hemodialysis.

New advances in evaluation and management of patients with polycystic liver disease

Adult polycystic liver disease (APLD) is an autosomal dominant condition most commonly associated with polycystic kidney disease. However, over the last decade it has come to be recognized that APLD is a genetically heterogeneous disorder involving derangements on at least three different chromosomes. Mutations involving chromosomes 16 and 4 accounting for autosomal dominant polycystic kidney disease (ADPKD) type 1 and type 2 have been well described as have their gene products, polycystin-1 and polycystin-2. These have since been joined by a more recently recognized mutation in the short arm of chromosome 19 thought to be responsible for a much rarer form of autosomal dominant polycystic liver disease without any associated renal involvement. Despite the sometimes impressive physical and radiologic findings, only a minority of patients will progress to advanced liver disease or develop complications as a result of massive hepatomegaly. In these patients, medical management alone has proved ineffectual. Therefore, in the symptomatic APLD patient, surgical therapy remains the mainstay of therapy and includes cyst aspiration and sclerosis, fenestration with and without hepatic resection and orthotopic liver transplantation. The surgical literature on treatment of APLD, to include outcome measurements and complication rates are summarized. Additionally, we review other potential organ involvement and resultant complications.

Recurrence of intracranial aneurysms in autosomal-dominant polycystic kidney disease

BACKGROUND

The natural history of intracranial aneurysms (ICAs) in individuals with autosomal-dominant polycystic kidney disease (ADPKD) is poorly defined.

METHODS

We followed twenty ADPKD subjects, eleven with ruptured and nine with intact ICA, for 15.2 +/- 8.1 years (range, 6.0 to 33.2 years). Initial diagnosis was by four-vessel cerebral angiography in eighteen subjects. Follow-up examinations were four-vessel cerebral angiography in fourteen and magnetic resonance angiography (MRA) in six subjects. We examined the occurrence of new ICAs, an increase in size of existing ICAs, recurrent rupture or surgical intervention, and death.

RESULTS

Age at initial diagnosis of ICA was 37.7 +/- 10.4 years (range, 20.2 to 53.1 years). Seventeen subjects (85%) had an anterior and three (15%) had a posterior ICA at initial diagnosis. On restudy, five subjects (25%) had a significant change, consisting of new ICAs in a different location in all five and an increase in size of an existing ICA in two of the five. All subjects with ruptured ICA and one subject with intact ICA had undergone surgery at the time of initial diagnosis. Ten subjects (50%) underwent further surgery 8.1 +/- 6.1 years later (1.3 to 17 years). No subject died during follow-up and one subject experienced a recurrent RICA (RICA). We were unable to identify risk factors associated with development of a new ICA or increase in size of an existing ICA.

CONCLUSION

Individuals with ADPKD and ICA appear to be at moderate risk for new ICAs and increase in size of existing ICAs; mortality and risk of recurrent rupture, however, appear to be low.

Chronic subdural hematoma in autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) has been associated with an increased incidence of aneurysmal subarachnoid hemorrhage and intracerebral hematomas. We describe five patients with chronic subdural hematomas, a previously unrecognized complication of ADPKD. In four of the five cases, no trigger was apparent. Clinical presentation was subtle, with mild hemiparesis, headache, or both in four patients and transient neurological deficits mimicking transient ischemic attacks in one patient. In three of the five patients, a retrocerebellar arachnoid cyst was found, suggesting a plausible causal relation between the intracranial arachnoid cysts and the subdural hematomas. In one patient, subdural hematoma was in close proximity to the frontally located arachnoid cyst.

Evaluation of colonic diverticular disease in autosomal dominant polycystic kidney disease without end-stage renal disease

A previous study had shown an increased prevalence (83%) of diverticula among patients with autosomal dominant polycystic kidney disease (ADPKD) with end-stage renal disease (ESRD) compared with other ESRD patients without ADPKD (32%). Others have also suggested an increased risk for diverticular complications in renal transplant recipients with ADPKD. To determine whether there was an increased occurrence of diverticula among non-ESRD patients with ADPKD, we studied 55 patients with ADPKD who were not receiving renal replacement therapy compared with 12 unaffected family members (non-ADPKD) and 59 random patients who had undergone barium enemas (control [C]). No study patient had a history of diverticular disease. All patients underwent a double-contrast barium enema after administration of glucagon. The occurrence, number, location, and size of diverticula were noted. There was no significant difference among the three groups in regard to sex (men: ADPKD, 42% versus non-ADPKD, 42% versus C, 37%) or age (ADPKD, 49.3 +/- 0.7 versus non-ADPKD, 51.2 +/- 2.1 versus C, 49 +/- 1 years). There was no significant difference in the percentage of patients with diverticula (ADPKD, 47% versus non-ADPKD, 58% versus C, 59%), the percentage with only right-colon diverticula (ADPKD, 5% versus non-ADPKD, 17% versus C, 5%), the mean number of diverticula in patients with diverticulosis (ADPKD, 13.8 versus non-ADPKD, 7.9 versus C, 9.9 diverticula), or the size of the largest diverticula (ADPKD, 9.5 versus non-ADPKD, 10.4 versus C, 10.5 mm). There was no significant difference in these variables between the patients with ADPKD with a creatinine clearance greater than 70 mL/min/1.73 m(2) (n = 25) or less than 70 mL/min/1.73 m(2). This study does not show the greater prevalence of diverticular disease in non-ESRD patients with ADPKD compared with the general population. Thus, patients with ADPKD need not be considered at greater risk for diverticular disease than the general population.

Risk and prognosis in renal neoplasms. A pathologist's prospective

The incidence of renal carcinoma has increased in the United States over the last two decades. An increased rate of detection of incidental tumors and a variety of exogenous risk factors may be responsible for this increase. Pathologic stage and nuclear grade remain the most important and practical prognostic features, however, the specific tumor type has emerged as important as the cytogenetic validation of recent renal carcinoma classification. Proliferation markers, DNA ploidy, and morphometry have powerful predictive value but are handicapped by cost and complexity. The search continues for molecules of diagnostic and prognostic utility that may also impact invasive and metastatic capability for this group of neoplasms whose course is principally determined by the completeness of the original resection.

The use of ultrasonography and linkage studies for early diagnosis of autosomal dominant polycystic kidney disease (ADPKD)

To define possibly affected members of 69 families and to identify the factors influencing the progression of autosomal dominant polycystic kidney disease (ADPKD), 276 subjects at risk of having inherited the mutant gene underwent ultrasonographic scanning (US), using an ultrasound real-time scanner. At a mean age of 26 +/- 12 years (range 4-71), 85/276 individuals (31%) presented ultrasound evidence of the disease (at least two cysts in one kidney and one cyst in the other) (US: positive), while only 19/85 (22%) had one or more manifestations of ADPKD prior to diagnosis. The prevalence of the disease in subjects at risk aged < 30 years was 53/154 (34%), while hepatic cysts were also detected in 7/85 ADPKD probands (8%) (five females) at a mean age of 40 +/- 6 years (range 30-45) and their frequency correlated with the number of pregnancies. History was proved to be important in suspecting the disease since symptoms were more common in US positive as compared to negative subjects (22% vs 6%, p < 0.001). On the other hand, physical examination and routine laboratory data at presentation revealed abnormal signs mainly in US positive individuals aged 30-39 years. Forty ADPKD families met the criterion for genetic study (at least two members affected) but in three of them (7.5%), no linkage to DNA-markers for the short arm of chromosome 16 was detected ("unlinked" or ADPKD2). DNA-analysis in the rest 37 "linked" (ADPKD1) families identified the gene-carrier state in 18/123 (15%) US negative subjects at risk, at a mean age of 13 +/- 7 years (range 3-25). There were significantly more US positive subjects aged > or = 30 years in ADPKD2 as compared to ADPKD1 families (83% vs 35%, p < 0.05) suggesting that the progression of the disease is slower in the former families. During a 5-year follow-up, 6/18 gene-carriers (33%) had already developed distinct renal cysts on US, at a mean age of 20 +/- 9 years (range 8-29). On the contrary, none of the ADPKD1 non-carriers and the US negative ADPKD2 subjects had shown any ultrasound findings of cystic renal disease at that period.

Diversity of calcium antagonists

Calcium antagonists (CAs) are widely used in the management of hypertension and chronic stable angina pectoris. Currently available CAs fall into three distinct structural classes--the dihydropyridines, the benzothiazepines, and the phenylalkylamines. The diversity of these agents, even among drugs within a structural group, is apparent in their pharmacology, physiologic effects, and therapeutic uses. Traditional CAs produce their effects through blockade of the L-type calcium channel. Recently, a new CA has been developed. Mibefradil, the first member of a new class of CAs, is a tetralol derivative. It is characterized by its selective blockade of T-type calcium channels. It differs from existing CAs and may offer important therapeutic advantages.

Autosomal dominant polycystic kidney disease in Persian and Persian-cross cats

A form of autosomal dominant polycystic kidney disease (ADPKD) similar in clinical features to human ADPKD occurs in the Persian cat. We characterized the morphologic and immunohistochemical features of this disease in a colony of affected cats. Complete postmortem examinations were performed on 11 normal and 22 affected cats ranging in age from 3 months to 10 years. Kidneys were evaluated by gross and histologic examinations, ultrastructure, lectin staining, bromodeoxyuridine immunochemistry for labeling index and immunochemistry for distribution of Na/K ATPase. Feline ADPKD was characterized by variable numbers of cysts in the renal cortex and medullar. Ultrastructural examination and lectin staining suggested that cysts arose from proximal and distal nephron segments. Bromodeoxyuridine labeling demonstrated increased proliferation of epithelium lining some cysts in young cats. Immunohistochemical staining showed variable translocation of Na/K ATPase from the basolateral membranes of cyst-lining cells to the cytoplasm or luminal membranes. Cystic renal disease commonly was associated with chronic tubulointerstitial nephritis and hepatobiliary hyperplasia and fibrosis. Focal hyperplasia of renal tubular epithelium, hepatic cysts, and cardiac lesions were present in some cats. Feline ADPKD shares many morphologic and pathogenetic features with human ADPKD.

International renal-cell-cancer study. VI. the role of medical and family history

A number of medical conditions have been linked with renal-cell cancer, although the evidence is not consistent in every case. In a large international case-control study of renal-cell cancer, we examined, among other hypotheses, associations with a personal history of certain medical conditions and a family history of cancer of the kidney or thyroid. Relative risks (RR), adjusted for the effects of age, gender, body-mass index, tobacco smoking and study centre, were significantly increased by a history of kidney stones or thyroid or kidney disease. The RR were not altered by additional adjustment for hypertension, or when diagnoses were restricted to those made at least 5 or 10 years before 1987 (the usual "cut-off" date). The link with kidney injury is particularly likely to be affected by recall bias. Increased RR of borderline significance were found for kidney infection (RR, 1.2) and diabetes (RR, 1.4). Having one first-degree relative with kidney cancer was associated with a significantly increased risk of renal-cell cancer (RR, 1.6; 95% Cl, 1.1-2.4). Seven cases reported 2 first-degree relatives with kidney cancer. No controls had first-degree relatives with kidney cancer. None of our participants reported having von Hippel-Lindau disease. The data suggests that a few conditions of the kidney are strongly associated with renal-cell cancer and that heredity plays a role in a small proportion of cases.

Adult polycystic kidney disease in Hong Kong Chinese: an autopsy study

To appraise the frequency, clinical features and prognosis of adult polycystic kidney disease (APKD) in Hong Kong, 41 Chinese patients who had an autopsy diagnosis of APKD were studied retrospectively. The APKD patients constituted 0.295% of 13,890 (or one in 339) autopsies performed during the study period (1964-1991). The frequency of APKD in autopsied populations in Western countries varies from one in 261 to one in 1,019 with an average of one in 503. Nineteen (46%) patients reached end-stage renal disease (ESRD) at the time of death. Ruptured berry aneurysm caused death in 3 patients while 3 others had spontaneous intracerebral hemorrhage. Left ventricular hypertrophy was found in 24 (59%) patients. Polycystic liver was present in 26 (63%) patients. This frequency was higher than the 4% to 60% (average 47%) reported in similar studies conducted in Western countries. The probability of patients being alive and without ESRD, estimated using a life table analysis, was 83%, 54%, 32% and 12% by the age of 40, 50, 60 and 70 respectively. No difference in frequency, clinical features and survival between male and female APKD patients could be demonstrated.

Autosomal dominant polycystic kidney disease (ADPKD)--mechanisms of cyst formation and renal failure

None of the hypotheses proposed so far to explain cyst formation in autosomal dominant polycystic kidney disease (ADPKD) is entirely satisfactory, e.g. the theory of tubular obstruction by intraluminal polyps or dilatation of nephron segments as a consequence of abnormal compliance of the basement membrane. Recent in vitro studies show that (i) synthesis of basement membrane material is abnormal and that (ii) the direction of transepithelial resorptive flux into a secretory mode is reversed as a consequence of faulty insertion of Na, K-ATP'ase into the luminal membrane. It remains unclear why cystic transformation of a few percent of nephrons should cause endstage renal failure. Our clinical and experimental studies do not provide evidence to support some hypotheses proposed in the past, i.e. that renal parenchyma is compressed by expanding cysts and that glomeruli are overperfused. Our histological studies show that progression to endstage renal failure is associated with (i) progressive arteriolar lesions (out of proportion to the vascular lesions seen in extrarenal vascular beds; and (ii) progressive interstitial fibrosis. It appears that fibroblasts in ADPKD are particularly sensitive to platelet derived growth factor (PDGF) which is secreted by epithelial cells of the cyst wall in a paracrine fashion. In contrast to previous opinion, which was presumably skewed by ascertainment bias, it appears that not all, and perhaps not even a majority, of ADPKD patients progress to endstage renal failure. Factors related to progression are gender, family history and hypertension. Both abnormal sodium excretion and inappropriate renin secretion play a role in the genesis of hypertension. Elevated blood pressure, albeit within the normotensive range, is demonstrable even in prepubertal children. The involvement of renin in renal vasoconstriction of normotensive ADPKD patients suggests a particular role of ACE inhibitors in the management of these patients.

Stroke in adult polycystic kidney disease

In order to assess the incidence of acute cerebrovascular events, 142 patients with adult polycystic kidney disease were retrospectively reviewed. Fourteen patients (9.8%) had 19 cerebral attacks. Six patients (4.2%) had intracranial haemorrhage attacks (three ruptured intracranial aneurysms and three cerebral haemorrhages). Ischaemic events occurred in nine patients (five cerebral infarctions and four transient ischaemic attacks). Patients with ischaemic attacks had a better outcome than patients with haemorrhagic events even when transient ischaemic attacks were excluded. Patients with ruptured intracranial aneurysms were younger. Cerebral complications are an important cause of morbidity and mortality in patients with adult polycystic kidney disease. They can prove disabling prior to or after dialysis and transplantation.

Clinical profiles of gross hematuria in autosomal dominant polycystic kidney disease

There is little information on the characteristics, management, or sequelae of gross hematuria in autosomal dominant polycystic kidney disease (ADPKD). Therefore, we obtained detailed information regarding gross hematuria in 191 adult ADPKD subjects. Forty-two percent (N = 81) experienced at least one episode of gross hematuria. The mean age of the initial episode was 30 +/- 1 years; only 10% of subjects reported the first episode before age 16. Twenty-three percent of those with gross hematuria had experienced more than six occurrences. Sixty-two percent of patients with bleeding indicated a presumptive precipitating event, most commonly urinary tract infection (42% overall, 61% of females v 17% of males, P less than 0.01), or sports or strenuous activity (20% of males v 11% of females, NS). In 56% of subjects, the episode persisted for 2 to 7 days. Hypertensive ADPKD subjects were more likely to have gross hematuria than normotensive subjects (48% v 30%, P less than 0.02) and those with gross hematuria had larger renal size (820 +/- 87 v 588 +/- 52 cm3, P less than 0.03). Moreover, those subjects with more episodes of gross hematuria had a higher serum creatinine concentration than those with fewer episodes (serum creatinine: 0 episodes, 120 +/- 10 v greater than 5 episodes, 190 +/- 30 mumol/L, P less than 0.04 [1.4 +/- 0.1 v 2.1 +/- 0.3 mg/dL]). This association suggests that, although self-limited, cumulative episodes of gross hematuria may have an unfavorable impact on long-term renal function.

Successful pregnancy in a patient with polycystic kidney disease and advanced renal failure: the use of prophylactic dialysis

Adult polycystic kidney disease is an inherited disease that is transmitted as an autosomal dominant trait. The clinical manifestations, which develop during the third or fourth decade of life, usually do not affect women during childbearing age and thus do not affect fertility or pregnancy outcome. The patient presented here had polycystic kidney disease and advanced renal failure, and was treated with meticulous fetal surveillance and prophylactic hemodialysis during pregnancy. The successful outcome strengthens the trend to perform prophylactic dialysis in pregnancies with advanced renal failure, despite the lack of controlled studies.

Perceptions of genetic risk in individuals with a one in two chance of developing autosomal dominant polycystic kidney disease

OBJECTIVE

To determine the level of understanding of personal genetic risk in people born with a one in two risk of having autosomal dominant polycystic kidney disease (ADPKD).

DESIGN

Consenting individuals, contacted through affected family members, were asked standard questions about their knowledge of their own genetic risk. These questions were incorporated into a study investigating the use of DNA diagnostic techniques in ADPKD which was an opportunity to interview a substantial number of Australians at risk of inheriting this condition.

SETTING

Interviews were conducted in the individuals' homes, or at the Royal Melbourne Hospital Renal Clinic or the Royal Children's Hospital Genetics Clinic.

PATIENTS

Three hundred and eighty-seven individuals aged 15 years or more, born with a one in two risk but who had remained undiagnosed up until the time of study were identified within 46 families. Sixty-six were excluded from the study either because they resided too far away or they declined involvement. The remaining 321 were assessed clinically, 304 of whom were also interviewed about their understanding of their risk of having inherited this condition.

RESULTS

Thirty per cent knew their risk at birth was one in two. Nine per cent were unaware that ADPKD was an inherited condition. Forty-one per cent were aware that ADPKD was inherited but had no opinion about their personal risk. Three per cent thought that they had no chance of having the condition, 3% thought that they were definitely affected, 8% considered their risk lay from 1%-49% and 6% thought their risk lay from 51%-99%.

CONCLUSION

Within this group of people with a high risk of having an inherited condition with preventable and treatable components, the majority has a poor understanding of their genetic risk.

Organic manic syndrome associated with advanced uraemia due to polycystic kidney disease

Mania secondary to advanced uraemia caused by polycystic disease of the kidneys in a 62-year-old woman involved a complex interplay of physical, psychological and social factors. Psychotherapy and thioridazine led to full recovery.

The renin-angiotensin-aldosterone system and autosomal dominant polycystic kidney disease

BACKGROUND

A high incidence of hypertension (50 to 75 percent) occurs early in the course of autosomal dominant polycystic kidney disease. Cyst enlargement, causing bilateral renal ischemia and subsequent release of renin, is proposed as the cause of this form of hypertension.

METHODS

To investigate this hypothesis, we measured plasma renin activity and aldosterone concentrations during short-term and long-term converting-enzyme inhibition in 14 patients with hypertension due to polycystic kidney disease, 9 patients with essential hypertension, 11 normotensive patients with polycystic kidney disease, and 13 normal subjects. The groups were comparable with respect to age, sex, body-surface area, degree of hypertension, sodium excretion, and renal function.

RESULTS

During the short-term study, the mean (+/- SE) plasma renin activity was significantly higher in the hypertensive patients with polycystic kidney disease than in the patients with essential hypertension, in the supine (0.36 +/- 0.06 vs. 0.22 +/- 0.06 ng per liter.second, P = 0.05) and upright positions (1.03 +/- 0.14 vs. 0.61 +/- 0.08 ng per liter.second, P less than 0.03) and after converting-enzyme inhibition (1.97 +/- 0.28 vs. 0.67 +/- 0.17 ng per liter.second, P less than 0.0006). The mean arterial pressures measured in the supine and upright positions and the plasma aldosterone concentrations measured in the upright position were significantly higher in the normotensive patients with polycystic kidney disease than in the normal subjects. After six weeks of converting-enzyme inhibition, renal plasma flow increased (P less than 0.005), and both renal vascular resistance (P less than 0.007) and the filtration fraction (P less than 0.02) decreased significantly in the hypertensive patients with polycystic kidney disease but not in the patients with essential hypertension.

CONCLUSIONS

The renin-angiotensin-aldosterone system is stimulated significantly more in hypertensive patients with polycystic kidney disease than in comparable patients with essential hypertension. The increased renin release, perhaps due to renal ischemia caused by cyst expansion, probably contributes to the early development of hypertension in polycystic kidney disease.

The diagnosis and prognosis of autosomal dominant polycystic kidney disease

BACKGROUND

Autosomal dominant polycystic kidney disease is usually caused by a mutant gene at the PKD1 locus on the short arm of chromosome 16, but in about 4 percent of families with the disorder it is caused by unknown mutations elsewhere in the genome. The natural course of the disease in both genetic forms is not well characterized.

METHODS

We studied 17 families with autosomal dominant polycystic kidney disease to compare presymptomatic diagnosis by ultrasonography with diagnosis by genetic-linkage studies and to relate clinical variation of the disease to whether the PKD1 mutation was implicated.

RESULTS

In 10 families the disorder was found to cosegregate with polymorphic DNA markers flanking the PKD1 locus, in 2 families it did not, and in 5 families linkage could not be determined. In the 10 families with the PKD1 mutation, 46 percent of the members less than 30 years old who had a 50 percent risk of inheriting a mutation had renal cysts, as compared with 11 percent of the members of the two families without linkage (P less than 0.001). In the PKD1 families, all 67 diagnoses made by ultrasonography were confirmed by determination of the genotype as inferred from linkage. Forty of 48 members (83 percent) less than 30 years old who inherited the PKD1 mutation had renal cysts. All 27 members 30 years old or older who inherited the mutation had renal cysts, suggesting that the probability of a false negative diagnosis did not exceed 0.13 in this age group (P less than 0.05). The mean (+/- SE) age at the onset of end-stage renal disease among members of the PKD1 families was 56.7 +/- 1.9 years, as compared with 69.4 +/- 1.7 years among members with cysts in the families without linkage (P = 0.0025). Hypertension and renal impairment were less frequent and occurred later in the families without the PKD1 mutation.

CONCLUSIONS

At present, in most persons with a 50 percent risk of autosomal dominant polycystic kidney disease, imaging techniques are the only mode of reaching a diagnosis before symptoms appear. In such persons a negative ultrasonographic study during early adult life indicates that the likelihood of inheriting a PKD1 mutation is small. In the few who inherit a non-PKD1 mutation for polycystic kidney disease, renal failure is likely to occur relatively late in life.

Molecular genetics of chronic liver diseases

The molecular genetics of five common single gene and one polygenic chronic liver disease is discussed. In two of the single gene disorders, alpha 1-antitrypsin deficiency and cystic fibrosis, the gene responsible is now known and the repertoire of different mutations underlying the disease is being defined. In the other three single gene defects (haemochromatosis, polycystic liver disease and Wilson's disease) the chromosomal location of the disease allele is known. It is anticipated that recombinant DNA techniques will enable the genes responsible for these diseases to be cloned in the near future, thus allowing the biochemical abnormalities to be defined through reverse genetics. In many chronic liver diseases the relative contribution of genetic and environmental factors remains unclear. Evidence suggests there is a definite genetic component in predisposition to alcoholic cirrhosis; the role of putative candidate genes is discussed. It is hoped that the definition of a genetic locus linked to alcoholic cirrhosis will ultimately teach us more about the basic pathogenesis of this disease.

Unexpected ultrasonographic prenatal diagnosis of autosomal dominant polycystic kidney disease

The prenatal diagnosis of autosomal dominant polycystic kidney disease (ADPKD) is now being reported with increasing frequency. We report three cases and review 12 cases of ADPKD diagnosed in the fetus by ultrasonographic findings. Increased echogenicity and renal enlargement are the main ultrasonographic signs of ADPKD. Renal cysts are uncommon. Diagnosis is easy in a family with a positive ADPKD history. Conversely, there may be no apparent family history, as in our three cases and three cases from the literature. We consider the problems of unexpected diagnosis, family investigation, and the prognosis of ADPKD in children with prenatally diagnosable forms.