Contributors: Phil Nicholls, Julien Bazelle
Species: Canine | Classification: Diseases
Introduction Pathogenesis Diagnosis Treatment Outcomes Further Reading
Introduction
- Cause: juvenile renal disease is usually caused by a congenital (developmental) or hereditary renal abnormality.
- The diseases include renal dysplasia, renal agenesis, renal cortical hypoplasia, glomerulopathies or reflux nephropathy with segmental hypoplasia (Ask-Upmark kidney).
- Signs: the animals present with signs of chronic renal failure, stunted growth, dysphagia, signs related to renal secondary hyperparathyroidism.
- Diagnosis: history, clinical signs, biochemistry, hematology, blood pressure, urinalysis, radiography, ultrasonography, histopathology.
- Prognosis: guarded.
Presenting Signs
- Same as chronic renal failure Kidney: chronic kidney disease (CKD).
- Renal osteodystrophy Renal secondary hyperparathyroidism/'rubber jaw' is more commonly noticed in young animals with renal disease.
Age Predisposition
- <1 year old (<7 months).
- Severely affected animals die young.
Breed Predisposition
- Dobermann Dobermann : glomerulosclerosis, interstitial fibrosis, renal agenesis Kidney: agenesis.
- Cocker Spaniel English Cocker Spaniel : cortical hypoplasia Kidney: renal hypoplasia.
- Elkhound Elkhound : interstitial fibrosis, primary renal glucosuria.
- Basenji Basenji: Fanconi syndrome Kidney: Fanconi and Fanconi-like syndromes.
- Shih Tzu Shih Tzu : renal dysplasia Kidney: dysplasia.
- Lhasa Apso Lhasa Apso : renal dysplasia.
- Samoyed Samoyed : glomerulopathy.
- Standard Poodle Poodle: Standard : renal dysplasia.
- Welsh Corgi - Pembroke Welsh Corgi: Pembroke : renal telangiectasia.
- Soft Coated Wheaten Terrier Soft Coated Wheaten Terrier : renal dysplasia.
- Bull Terrier Bull Terrier : glomerulopathy.
- German Shepherd Dog (Alsatian) German Shepherd Dog : renal cortical hypoplasia.
- Beagle Beagle: renal dysplasia, unilateral agenesis, polycystic kidney disease Kidney: polycystic disease, Imerslund-Gräsbeck syndrome Imerslund-Gräsbeck syndrome.
- Boxer Boxer: renal dysplasia, reflux nephropathy with segmental hypoplasia (Ask-Upmark kidney).
- Yorkshire Terrier Yorkshire Terrier: renal dysplasia.
- Great Dane Great Dane: renal dysplasia.
- Scottish Terrier Scottish Terrier: primary renal glucosuria, cystinuria.
Special Risks
- Same as chronic renal failure Kidney: chronic kidney disease (CKD).
Pathogenesis
Etiology
- Not well-defined.
- Insults during the fetal and neonatal period, eg:
- Herpesvirus infection Canine herpesvirus disease.
- Circulating nephrotoxins.
- Ischemia.
- Urinary obstruction.
- Hereditary:
- A familial basis has not been established in all cases.
- Hereditary nephropathy: abnormalities of type IV collagen genes.
- An autosomal recessive mode of inheritance is probable in Lhasa Apso Lhasa Apso and Shih Tzu Shih Tzu breeds.
- Familial disease has been reported in Soft-coated Wheaten Terrier Soft Coated Wheaten Terrier , Standard Poodle Poodle: Standard , Chow Chow Chow Chow , Alaskan Malamute Alaskan Malamute , Golden Retriever Retriever: Golden and Dutch Kooiker Kooikerhondje.
- But the disease has been reported in many other breeds also, for which a familial basis has not been shown.
- Same as chronic renal failure (less common in young dog)
Predisposing Factors
General
- Breed.
Pathophysiology
- Renal disease in immature or young adult dogs which is not associated with primary renal inflammation:
- Agenesis.
- Hypoplasia.
- Dysplasia.
- Primary cystic diseases.
- Glomerulopathies.
- Tubulointerstitial nephropathies.
- Tubular transport dysfunction.
- Renal dysplasia is characterized by disorganized development of renal parenchyma due to anomalous differentiation.
- Induction of the metanephric blastema is initiated but fails to undergo complete differentiation → persistence of poorly differentiated tissue, ie fetal glomeruli and/or tubules, persistent mesenchyme, or anomalous structures, ie atypical tubular epithelium.
- Persistent metanephric ducts and dysontogenic metaplasia - rare in dogs.
- Due to agenesis, developmental abnormalities and non-functioning renal tissue signs of chronic renal failure usually develop before the animal is one year old.
- Increased renal calcium loss → hyperparathyroidism → osteoporosis → increased risk of fibrous osteodystrophy (rubber jaw) and fractures.
Timecourse
- Once clinical signs develop, the disease progresses rapidly.
Diagnosis
Presenting Problems
- Stunted growth.
- Same as chronic renal failure Kidney: chronic kidney disease (CKD). Especially PUPD and inappropriate urination.
- Fibrous osteodystrophy/rubber jaw.
Client History
- Stunted growth.
- Same as chronic renal failure Kidney: chronic kidney disease (CKD):
- Polyuria/polydipsia.
- Weight loss/poor weight gain.
- Inappetence.
- Vomiting/diarrhea.
- Depression.
- Difficulty eating (rubber jaw).
Clinical Signs
- Stunted growth.
- Occasionally poor body condition score Body condition scores, poor coat quality.
- Same as chronic renal failure Kidney: chronic kidney disease (CKD) :
- Polyuria, polydipsia, anorexia, vomiting, depression, diarrhea, weight loss, hypothermia, pale mucous membranes.
- Rubber jaw.
Diagnostic Investigation
- Same as chronic renal failure Kidney: chronic kidney disease (CKD).
Biochemistry, hematology, blood gas
- Increased urea Blood biochemistry: urea, creatinine Blood biochemistry: creatinine and phosphorus Blood biochemistry: phosphate.
- Metabolic acidosis Acid base imbalance.
- Normocytic, normochromic anemia Hematology: red blood cell count.
Radiography
- Kidneys may be small and misshapen.
- Osteoporosis, paper thin cortices, especially visible on skull radiography.
- Fractures.
2D Ultrasonography
- Renal architecture may be abnormal, generally with changes in echogenicity, irregular margins Ultrasonography: kidney.
- Increased resistive index
.
Urinalysis
- Same as chronic renal failure.
- Proteinuria Urinalysis: protein.
- Glucosuria Urinalysis: glucose (only in Fanconi syndrome).
- Susceptibility to secondary urinary tract infection Cystitis: bacterial.
Gross Autopsy Findings
- Chronic renal failure and uremia in a young dog.
- There may be rubber jaw (flexibility of mandibles and other skull components).
- Affected kidneys may be shrunken, pale, firm, with a stippled cortex.
- There may be cortical scars, medullary fibrosis and cysts.
Histopathology Findings
- Depending on the type, there can be membranoproliferative glomerulonephritis, thickening of Bowman's capsule, periglomerular fibrosis, tubular atrophy and cyst formation.
- Interstitial fibrosis may be seen.
Differential Diagnosis
- Same as chronic renal failure Kidney: chronic kidney disease (CKD).
- Hypothyroidism (stunted growth) Hypothyroidism.
- Congenital dwarfism (decreased growth hormone).
- Hypophosphatemic rickets (stunted growth, decreased opacity skeleton).
- Congenital porto-systemic shunt (polyuria/polydipsia, stunted growth Congenital portosytemic shunt (CPSS).
Treatment
Standard Treatment
- See chronic renal failure for management Kidney: chronic kidney disease (CKD).
Outcomes
Prognosis
Good
- If enough normal functioning renal tissue is present, eg in agenesis of one kidney.
- Renal telangiectasia may only develop problems quite late in life.
- Some Shih Tzu have lived several years before developing clinical signs.
Poor
- Once renal failure develops, disease usually progresses quite rapidly.
- Mean age at death is 2 years or less.
Expected Response to Treatment
- Stabilizing azotemia and general demeanor of the animal.
Reasons for Treatment Failure
Further Reading
Publications
Refereed papers
- Recent references from PubMed and VetMedResource.
- Fyfe J C, Hemker S L, Venta P J, Stebbing B, Giger U (2014) Selective intestinal cobalamin malabsorption with proteinuria (Imerslund-Gräsbeck syndrome) in juvenile Beagles. J Vet Intern Med 28(2), 356-362 PubMed.
- Brachthäuser L, Pingen C H, Hecht W, Reinacher M (2013) Rubber jaw in a Weimaraner dog due to juvenile nephropathy. A case without evidence for genetic involvement. Tierarztl Prax Ausg K Kleintiere Heimtiere 41(3), 198-202 PubMed.
- Fyfe J C, Hemker S L, Venta P J, Fitzgerald C A, Outerbridge C A, Myers SL, Giger U (2013) An exon 53 frameshift mutation in CUBN abrogates cubam function and causes Imerslund-Gräsbeck syndrome in dogs. Mol Genet Metab109(4), 390-396 PubMed.
- Lees G E (2013) Kidney diseases caused by glomerular basement membrane type IV collagen defects in dogs. J Vet Emerg Crit Care (San Antonio) 23(2), 184-193 PubMed.
- Kolbjørnsen O, Heggelund M, Jansen J H (2008) End-stage kidney disease probably due to reflux nephropathy with segmental hypoplasia (Ask-Upmark kidney) in young Boxer dogs in Norway. A retrospective study. Vet Pathol 45(4), 467-474 PubMed.
- Peeters D et al (2000) Juvenile nephropathy in a Boxer, a Rottweiler, a Collie and an Irish Wolfhound. Aust Vet J 78 (3), 162-165 PubMed.