Retrospective analysis on the occurrence of kidney cysts in mice in a central animal facility in the years 2009-2019.

Kidney cysts in humans are mainly caused by inheritable polycystic kidney disease. Although they are a regular finding in laboratory mice, their occurrence upon dissection has not been systematically investigated, yet. Therefore, the aim of this report was to investigate on prevalence, phenotype and aetiology of spontaneously occurring kidney cysts in mice by retrospectively analysing the laboratory-receipt tables of the in-house laboratory of a central animal facility in North Rhine-Westphalia, Germany, years 2009-2019. A percentage of 0.4% of dissected mice displayed kidney cysts, with more male than female animals affected and average age equal to that of all dissected animals. Preliminary report in half of the cases was distended abdomen, and a few individuals displayed additional pathologic alterations of kidneys, most commonly dilated renal pelvis, or extrarenal comorbidities. Kidney cysts occurred independently of a renal phenotype of the transgenic strain or presence of infectious agents in health monitoring. To conclude, kidney cysts were characterized as harmless for affected mice but, as inheritability is suggested according with the literature, affected animals should be excluded from breeding.

Renoprotective effects of docosahexaenoic acid in cats with early chronic kidney disease due to polycystic kidney disease: a pilot study.

OBJECTIVES: Lipids containing n-3 fatty acids have been reported to have protective effects on renal function, with docosahexaenoic acid (DHA) expected to be particularly effective. However, no reports have demonstrated the renoprotective effects of DHA-enriched lipids in cats with chronic kidney disease (CKD). Therefore, the aim of this pilot study was to examine the renoprotective effects of DHA-enriched fish oil in cats. METHODS: Five healthy cats and five cats with early non-azotaemic CKD due to autosomal dominant polycystic kidney disease (PKD) were orally administered DHA-enriched fish oil in liquid form (250 or 500 mg/kg body weight [BW] and 250 mg/kg BW of DHA, respectively) for 28 days. Inappropriately dilute urine and markedly increased urinary N-acetyl-d-glucosamine (NAG) index were detected in cats with PKD before DHA-enriched fish oil administration. Changes in the fatty acid composition ratio in the blood of all 10 cats were assessed after orally administering 250 mg/kg of DHA. RESULTS: Post-administration, no adverse clinical effects were observed, and blood and urine tests were within the reference intervals in healthy cats. Cats with PKD showed significantly decreased serum symmetric dimethylarginine (SDMA), urine protein:creatinine ratio (UPC) and urinary NAG index at post-administration. Furthermore, oral administration of DHA-enriched fish oils significantly decreased the blood concentration ratio of arachidonic acid (AA) in cats with PKD post-administration. Furthermore, the concentration ratio of DHA in the blood significantly increased in both healthy cats and cats with PKD, and the DHA:AA ratio also increased. CONCLUSIONS AND RELEVANCE: Oral administration of DHA-enriched fish oils for 28 days significantly decreased blood AA levels and significantly increased DHA concentration and DHA:AA ratios in cats with PKD, and improved the SDMA, UPC and urinary NAG index, suggesting its potential for renoprotective effects in cats with early non-azotaemic CKD due to PKD.

Prevalence of polycystic kidney disease in Persian and Persian-related cats in western Mexico.

OBJECTIVES: Autosomal dominant polycystic kidney disease (ADPKD), the most frequently diagnosed hereditary disease affecting Persian cats, is caused by a cytosine-to-adenine transversion (10063C>A) in PKD1, the gene that codes for polycystin-1. The objective of this study was to provide a preliminary estimate of the frequency of the pathogenic 10063C>A single nucleotide polymorphism (SNP) of PKD1 in Persian and Persian-related cat breeds in western Mexico. METHODS: Blood samples were collected from 104 cats (89 Persian, seven Persian crossbreed, five Siamese and three Himalayan cats). Genotyping was performed with our proposed PCR restriction fragment length polymorphism (RFLP) assay, as well as a previously established PCR-RFLP method for validation. The genotypes of control cats were corroborated by a commercial veterinary genetics laboratory. RESULTS: Our proposed PCR-RFLP assay and the validated PCR-RFLP methodology indicated that 24/104 (23.1%) cats in this study were heterozygous carriers of the 10063C>A SNP, including 23/89 Persian cats (25.8%) and 1/7 Persian crossbreed cats (14.3%). No Siamese or Himalayan cats were carriers. There were no discrepancies between the results obtained with our proposed assay and those obtained with the validation method or with commercial laboratory results. CONCLUSIONS AND RELEVANCE: The carrier frequency of the PKD1 10063C>A SNP in Persian and Persian-related cat breeds in western Mexico was found to be 23.1%. ADPKD frequencies among cat populations in Mexico have not been published previously. Genotyping assays can be used to facilitate the selection of breeding stocks by local breeders and veterinarians to avoid propagation of ADPKD.

Polycystic Kidney Disease in 3 Juvenile Rainbow Lorikeets (Trichoglossus moluccanus).

This case series describes polycystic kidney disease in 3 (2 male, 1 female) 2-month-old, juvenile rainbow lorikeets (Trichoglossus moluccanus). The lorikeets diagnosed with polycystic kidney disease were the progeny of full sibling parents that were being intentionally line bred for the purpose of establishing a rainbow lorikeet with the blue color mutation. Clinically the juvenile lorikeets were presented with clinical signs of lethargy, dehydration, regurgitation, anorexia, polyuria, and pelvic limb paresis. Multiple abnormalities were identified on the complete blood count and plasma biochemistry panel, including a normocytic normochromic nonregenerative anemia, hyperuricemia, hyperphosphatemia, hypercalcemia, and azotemia. Severe renal dysfunction was diagnosed in all birds on the basis of clinical presentation, physical examination, and complete blood count and plasma biochemistry results. Radiographically marked renomegaly was noted in one of the cases. Although intensive critical care and supportive therapy was provided, 1 lorikeet died, and the remaining 2 were euthanatized because of client financial constraints and a rapid deterioration of their clinical condition associated with severe renal dysfunction. Postmortem pathology results found that all birds had marked renomegaly, visceral gout, and polycystic kidney disease. Because of the age of the birds and the line breeding within this group of lorikeets, the disease was believed to be inherited. Polycystic kidney disease should be considered as a possible differential diagnosis in juvenile psittacine birds with a history of line breeding when presented with severe renal dysfunction. From the current case series, polycystic kidney disease appears to carry a grave prognosis in juvenile rainbow lorikeets.

Bilateral Polycystic Kidneys and Focal Renal Cystadenoma in a Pygmy Sperm Whale ( Kogia breviceps).

An adult male pygmy sperm whale ( Kogia breviceps) stranded alive at a beach in Florida, US, in 2016. Main postmortem examination findings included bilateral multifocal variably sized renal cysts, focal renal cystadenoma, and mild dilation of the renal pelvises. The role of these renal lesions in the stranding of this whale is unknown.

Tubular cell loss in early inv/nphp2 mutant kidneys represents a possible homeostatic mechanism in cortical tubular formation.

Inversion of embryonic turning (inv) cystic mice develop multiple renal cysts and are a model for type II nephronophthisis (NPHP2). The defect of planar cell polarity (PCP) by oriented cell division was proposed as the underlying cellular phenotype, while abnormal cell proliferation and apoptosis occur in some polycystic kidney disease models. However, how these cystogenic phenotypes are linked and what is most critical for cystogenesis remain largely unknown. In particular, in early cortical cytogenesis in the inv mutant cystic model, it remains uncertain whether the increased proliferation index results from changes in cell cycle length or cell fate determination. To address tubular cell kinetics, doubling time and total number of tubular cells, as well as amount of genomic DNA (gDNA), were measured in mutant and normal control kidneys. Despite a significantly higher bromodeoxyuridine (BrdU)-proliferation index in the mutant, total tubular cell number and doubling time were unaffected. Unexpectedly, the mutant had tubular cell loss, characterized by a temporal decrease in tubular cells incorporating 5-ethynyl-2´-deoxyuridine (EdU) and significantly increased nuclear debris. Based on current data we established a new multi-population shift model in postnatal renal development, indicating that a few restricted tubular cell populations contribute to cortical tubular formation. As in the inv mutant phenotype, the model simulation revealed a large population of tubular cells with rapid cell cycling and tubular cell loss. The proposed cellular kinetics suggest not only the underlying mechanism of the inv mutant phenotype but also a possible renal homeostatic mechanism for tubule formation.

First report of Polycystic kidney disease occurrence in Persian cats in Serbia.

Polycystic kidney disease (PKD) is an inherited autosomal disorder in cats, mostly diagnosed in Persian cats. Renal cysts can be diagnosed by ultrasound, but cats must be at least 16 weeks old. The goals of this study were to assess the occurrence of PKD in Serbia using a randomly selected group of Persian cats, to compare the diagnostic efficacy of ultrasound and genetic tests, and to measure haematological and selected biochemical parameters. We examined 70 cats of Persian breed, between 4 months and 8 years of age. Complete blood count and selected biochemical parameters were measured, renal ultrasound was performed. Swabs of the oral cavity were obtained for genetic testing. Percentage of PKD positive cats identified by genetic testing was 48.6%, whilst only 18.6% were detected through ultrasound. Animals that were polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) positive and ultrasound negative ranged from 4 months to 3.5 years. All haematological and biochemical parameters were within the the normal range values in all examined cats. Genetic methods proved to be the most effective for reliable and early diagnosis of PKD in Persian cats. DNA analysis can be used right after birth, and excludes the need for other diagnostic procedures, such as ultrasound.

Polycystic kidney disease in Sprague-Dawley rats.

Polycystic kidney disease (PKD) is a cystic genetic disorder of the kidneys which is typically associated with cystic bile duct dilatation in the liver in humans, and domestic and laboratory animals. In humans, there are two types of PKD, autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD). ADPKD is caused by mutations in PKD1 or PKD2 gene while ARPKD is caused by mutation or loss of the PKHD1 (polycystic kidney and hepatic disease 1) gene. Here we report a morphologically confirmed case of spontaneous PKD in a Sprague-Dawley rat in which anatomic pathology examination revealed numerous cystic changes in the kidney and liver. Lesions consisted of marked cystic dilatations of renal tubules, and moderate cystic dilatations of intrahepatic bile ducts with portal fibrosis. We present detailed histologic features of the spontaneous PKD and compare them with disease model rats carrying an autosomal recessive PKHD 1 gene mutation.

Polycystic kidney disease in four British shorthair cats with successful treatment of bacterial cyst infection.

Polycystic kidney disease is the most common inherited disorder in cats. Renal cysts progressively increase in size and number, resulting in a gradual decrease in kidney function. An autosomal dominant mutation in exon 29 of the polycystin-1 gene has been identified, mostly in Persian and Persian-related breeds. This case study describes polycystic kidney disease in four British shorthair cats, of which two had the same genetic mutation reported in Persian and Persian-related cats. This likely reflects introduction of this mutation into the British shorthair breeding line because of previous outcrossing with Persian cats. An infected renal cyst was diagnosed and successfully treated in one of the cats. This is a commonly reported complication in human polycystic kidney disease, and to the authors' knowledge has not previously been reported in cats with polycystic kidney disease.

Polycystic kidneys and GM2 gangliosidosis-like disease in neonatal springboks (Antidorcas marsupialis).

Clinical, gross, histopathologic, electron microscopic findings and enzymatic analysis of 4 captive, juvenile springboks (Antidorcas marsupialis) showing both polycystic kidneys and a storage disease are described. Springbok offspring (4 of 34; 12%) were affected by either one or both disorders in a German zoo within a period of 5 years (2008-2013). Macroscopic findings included bilaterally severely enlarged kidneys displaying numerous cysts in 4 animals and superior brachygnathism in 2 animals. Histopathologically, kidneys of 4 animals displayed cystic dilation of the renal tubules. In addition, abundant cytoplasmic vacuoles with a diameter ranging from 2 to 10 µm in neurons of the central and peripheral nervous system, hepatocytes, thyroid follicular epithelial cells, pancreatic islets of Langerhans and renal tubular cells were found in 2 springbok neonates indicative of an additional storage disease. Ultrastructurally, round electron-lucent vacuoles, up to 4 µm in diameter, were present in neurons. Enzymatic analysis of liver and kidney tissue of 1 affected springbok revealed a reduced activity of total hexosaminidase (Hex) with relatively increased HexA activity at the same level of total Hex, suggesting a hexosaminidase defect. Pedigree analysis suggested a monogenic autosomal recessive inheritance for both diseases. In summary, related springboks showed 2 different changes resembling both polycystic kidney and a GM2 gangliosidosis similar to the human Sandhoff disease. Whether the simultaneous occurrence of these 2 entities represents an incidental finding or has a genetic link needs to be investigated in future studies.

Causes of mortality in anuran amphibians from an ex situ survival assurance colony in Panama.

The success of ex situ survival assurance populations as tools for amphibian conservation depends on the health and reproductive success of founder populations. Necropsy examination and histopathology of animals that die in assurance populations are useful for the identification of population-limiting disease problems and can help to direct applied research efforts in areas such as amphibian husbandry and nutrition. This study reviewed postmortem findings in 167 frogs from 13 species that died in a large Panamanian rescue and survival assurance population between 2006 and 2011. Common problems identified in long-term captive animals, especially in Atelopus species, were epithelial squamous metaplasia suggestive of vitamin A deficiency and a polycystic nephropathy resembling lesions seen in laboratory animals with electrolyte imbalances. Metabolic bone disease was a significant contributor to morbidity in captive-bred juvenile frogs of Gastrotheca cornuta, Hemiphractus fasciatus, and Hylomantis lemur. Findings common to multiple species included poor overall nutritional condition that was sometimes attributable to maladaptation to captive husbandry and epidermal hyperplasia and hyperkeratosis possibly reflecting environmental skin irritation. Infectious diseases and endoparasitism were most common in recently captured animals and included chytridiomycosis and Rhabdias sp. lungworms. Applied research efforts to improve sustainability of survival assurance populations should focus on elucidating optimal husbandry practices for diverse species, improving methods for nutritional supplementation of cultured insects and examination of the role of water composition in disease development.

Doença renal policística em bezerro / Polycystic kidney disease in a calf

Este relato descreve um caso de doença renal policística em um bovino, macho, mestiço, com um ano de idade. Ao exame clínicoobservou-se estado nutricional ruim, mucosas pálidas, desidratação moderada (8% a 10%), úlceras na região ventral da língua,áreas multifocais de hipotricose recobertas por crostas por todo o corpo e decúbito esterno-lateral permanente. Na avaliação dohemograma observou-se principalmente anemia arregenerativa e leucocitose devido à neutrofilia com desvio à [confirmar] esquerda.Na necropsia, os rins estavam aumentados de volume, pálidos e com a superfície natural finamente irregular. Histologicamente, haviasubstituição quase completa da cortical renal por múltiplos e pequenos cistos, distensão dos espaços de Bowman, regeneraçãotubular, fibrose, edema e leve infiltrado inflamatório linfoplasmocítico intersticial.

This report describes a case of polycystic kidney disease in a male, mixed breed bovine aged one year. On clinical examinationrevealed a poor nutritional status, pallid mucous membranes, moderated dehydration (8 to 10%), ulcers on the ventral portion ofthe tongue, multifocal areas of hypotrichosis covered with scabs throughout the entire body and permanent sternolateral decubitus.The blood exam revealed aregenerative anemia and leukocytosis (neutrophilia) with deviation to the left. The necropsy revealedenlarged, pallid kidneys with a finely irregular natural surface. The histological analysis revealed the nearly complete replacementof the renal cortex by numerous small cysts, distension of the Bowman space, tubular regeneration, fibrosis, edema and mildinterstitial lymphoplasmacytic inflammatory infiltrate.

Polycystic kidneys in the red panda (Ailurus fulgens).

An intact adult male 14.3-yr-old red panda (Ailurus fulgens) presented for health examination with a history of slowly progressing loss of body condition. Abdominal radiographs revealed a truncated abdomen with poor serosal abdominal detail and multiple areas of spondylosis with some collapsed intervertebral disc spaces. On computed tomography, multiple ovoid hypoattenuating lesions were seen in the left and right kidneys. Gross pathology and histopathology revealed multiple cystic lesions in the kidneys concurrent with pancreatic cysts on histopathology. To the best of the authors' knowledge, polycystic kidneys have not been reported in this species.

Polycystic kidney disease in a European roe deer (Capreolus capreolus).

A severe case of polycystic nephropathy was seen in an adult European roe deer (Capreolus capreolus), culled in a German hunting district. The doe had bilaterally drastically enlarged kidneys, completely riddled with variably sized, fluid-filled cysts of up to 4 cm in diameter. Histopathologic and ultrastructural examination revealed disseminated formation of cysts with flattened epithelial cell linings in the entire renal parenchyma, as well as severe dilations of renal tubules, marked interstitial fibrosis, nephron atrophy, and chronic interstitial lymphoplasmacytic infiltrations in the intercystic kidney tissue. These morphologic findings most likely resemble the hallmarks of autosomal dominant polycystic disease in humans, and present the first detailed description of a case of polycystic kidney disease in a roe deer.

Identification of porcine polycystic kidney disease 1 (PKD1) gene: molecular cloning, expression profile, and implication in disease model.

The polycystic kidney disease 1 (PKD1) gene, which accounts for ~85% of human autosomal dominant polycystic kidney disease (ADPKD) cases, has been extensively studied in human and mouse. Much information about the pathogenesis of and treatments for ADPKD has been gained from the use of mouse models. However, because mouse models pose some limitations, further studies in other model systems are needed to investigate the biological basis of ADPKD. The pig is regarded as an important biomedical model. Thus, we isolated a pig PKD1 homolog and characterized its cDNA sequence, genomic structure, expression profile, alternative splicing, methylation status, protein characteristics, and immunohistochemical features in both neonatal and adult pigs. The pig PKD1 cDNA is 14,209bp long and encodes a 4305-residue polypeptide. The genomic sequence of PKD1 is ~50kb with 46 exons. An alternative splice acceptor site was identified in intron 9. PKD1 is expressed in all tissues tested in both neonatal and adult pigs and exhibits a developmentally regulated expression pattern. Western blotting revealed that the molecular mass of polycystin-1 is ~460kDa, but its expression level is relatively low. Immunohistochemical study of the kidneys shows that polycystin-1 is mainly expressed in the tubular epithelia. Bisulfite methylation analysis of CpG islands in the promoter region does not show a direct correlation between methylation status and expression level among different tissues/cells. The cloning and characterization of pig PKD1 indicates that the pig and human genes are highly similar in length of genomic and cDNA sequences, genomic structure and context, expression patterns, conserved transcription factor binding sites, and the molecular mass of the encoded polycystin-1. These data support our current understanding of PKD1, and suggest that the pig is an ideal candidate for development of an ADPKD disease model.

Ultrasonographic findings in Cairn Terriers with preclinical renal dysplasia.

Renal dysplasia is a hereditary disease characterized by abnormal differentiation of renal tissue. The ultrasonographic appearance of dysplastic canine kidneys has been reported in the late stage of the disease where inflammatory and degenerative changes are already present and the dogs are in chronic renal failure. In this study, we describe the ultrasonographic appearance of the kidneys of five related Cairn Terriers affected with renal dysplasia before the onset of clinical or laboratory evidence of renal failure. Common findings included poor corticomedullary definition and multifocal hyperechoic speckles in the renal medulla, or a diffusely hyperechoic medulla. Severity of ultrasonographic changes was related to the severity of histopathologic findings. The ability to detect dysplastic changes before clinical signs develop makes ultrasound a potentially useful screening method for canine renal dysplasia.

Polycystic kidney disease in a Chartreux cat.

Polycystic kidney disease (PKD) is one of the most common genetic diseases in cats. It has been widely described in Persians and Persian-related cats and sporadically in other breeds. The purpose of the present paper is to describe the first reported case of PKD in a 12-year-old female Chartreux cat. The cat was referred with polyuria and polydipsia and enlarged and irregular kidneys at palpation. Multiple renal cysts and a single liver cyst were identified by ultrasound and the inherited pattern was confirmed by genetic test (polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) assay). Chartreux cats should be included in the screening programme of PKD, and PKD should be always considered as a possible cause of chronic renal failure in this breed.

Polycystic kidney disease in the pygmy hippopotamus (Hexaprotodon liberiensis).

Polycystic kidney disease (PKD) was diagnosed at necropsy in a captive aged female pygmy hippopotamus (Hexaprotodon liberiensis), which presented with numerous cysts in both kidneys, the liver, and the duodenum and with one single cyst in the pancreas. There were no premonitory clinical signs of a nephropathy observed prior to its death. Similar findings were made in a male cage mate 6 mo later. Both animals had been wild caught. A literature review revealed that another seven cases of PKD have been reported in pygmy hippopotamuses, and an additional screening of records available from the international studbook for the species revealed yet another six cases. In all cases, aged females were affected, and in several instances, affected animals were related to each other. These patterns indicated familiar transmission similar that associated with PKD in humans and other animals. The disease, and especially the presumptive bias in diagnosis toward females, indicated that the male animal of this report was the first case of PKD reported in a male pygmy hippopotamus; thus, further investigation is warranted. The status of the kidneys with respect to PKD should be assessed (including histology) in every deceased pygmy hippopotamus, and whenever possible by ultrasonography in live animals.

Evaluation of the repeatability of ultrasound scanning for detection of feline polycystic kidney disease.

Polycystic kidney disease (PKD) is the most prevalent inherited genetic disease in cats with Persian and Persian-related breeds predominantly affected. Diagnosis of PKD relied on ultrasound scanning until the recent development of the PKD gene test. However, gene testing has limitations as it will only identify the autosomal dominant form of PKD and not other forms of cystic kidney disease. Ultrasound scanning also has the advantage of being able to assess the severity and progression of disease in PKD affected cats. The aim of this study was to demonstrate the repeatability of ultrasound scanning in the detection of PKD and to assess progression of the disease over time. This study demonstrated 100% repeatability of ultrasound scanning in the detection of PKD and has also demonstrated progression of disease in 75% of PKD positive cats assessed over a 1-year period.

Polycystic kidney disease in adult Brazilian agoutis (Dasyprocta leporina).

During the last 21 years, 7 adult captive Brazilian agoutis (Dasyprocta leporina) from 4 different zoologic gardens were necropsied and histologically examined at the Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany. All animals had polycystic kidney disease as the major pathologic change. Except in 1 case, no clinical signs were recognized prior to death. The animals had macroscopic bilateral alterations of the kidneys ranging from granulated surfaces to severe polycystic changes. Microscopic examination revealed multifocal to generalized, moderate to severe cystic dilatations of Bowman's capsules and renal tubules, moderate mesangial and capsular proliferation of the renal corpuscles, mild interstitial fibrosis, and mild to moderate interstitial lympho-plasmacytic infiltrations. Little information is known about the genetic relationships of these animals, but breeding practice indicates a high possibility of inbred agouti zoo populations in Germany. This is the first report on polycystic kidney disease in Brazilian agoutis with possible genetic background.