7. Diseases of the kidney and the excretory system in ruminants Flashcards
Non-purulent renal diseases?
Acute nephrosis
Renal amyloidosis
glomerulonephritis, insterstilial nephritis
Non-Purulent renal diseases?
Non-purulent renal diseases
- Subclinical course, usually not diagnosed in vivo
- Symptoms of underlying disease are common
- Clinical signs of renal disease are rare
Acute nephrosis?
Acute nephrosis
Causes
• Intoxication, Pb, As, Cu toxicosis, haemoglobin nephrosis, monenzin, tannins (foliage of oak trees and
acorns), unidentified toxin of Amaranthus retroflexes, ochratoxin
Characteristics
- Rarely diagnosed clinically, no obvious signs
- Urine
o Proteinuria, renal epithelial cells/cylinders (casts)
Renal amyloidosis?
Renal amyloidosis
Cause
• Chronic inflammatory (purulent) diseases of other organs immunological processes, abnormal antibodyantigen reaction, hyperglobulinaemia, amyloids protein deposition, systemic disease
Consequences
• Renal enlargement, weight loss
• Nephrotic syndrome: massive proteinuria + oedema formation
• Uraemia: halitosis, uraemic stones, diarrhoea
Differential diagnosis
• Perform rectal exam and urinalysis
• Traumatic pericarditis, paratuberculosis
Non- Purulent nephritis+ glomerulonephritis and interstitial nephritis?
Non-purulent nephritis= glomerulonephritis, interstitial nephritis
- Primary disease or component of systemic diseases
- Immune-complex formation (glomerulonephritis)
- Infectious diseases (interstitial nephritis e.g., leptospirosis)
Characteristics
- Rarely diagnosed clinically (no obvious signs) can be detected by US-guided biopsy if necessary
- Urine
o Proteinuria, renal epithelial cells/cylinders (casts)
Purulent renal diseases?
Purulent nephritis
Contagious bovine pyelonephritis
Urolithiasis
Purulent Nephritis Ethiology?
Purulent nephritis
• Embolic nephritis/ embolic suppurative nephritis/ renal abscess)
Etiology
• Bacterial (metastatic emboli, hematogenous route from
o Valvular endocarditis
o Suppurative lesions in uterus, udder, navel
o Septicaemias in calves/ lambs
Characteristics and treatment of purulent nephritis?
Characteristics
- Rarely diagnosed clinically (no obvious signs)
- But +/- rectal finding
- Urine
o Proteinuria, pyuria, haematuria, bacteriuria
Treatment
• AB
Contagious bovine pyelonephritis?
Contagious bovine pyelonephritis
Etiology
- Milking cows of 4-8 years, after calving, after repeated AB, especially in autumn/winter
- Corynebacterium renal (C. Bovis Renalis)
o Urease positive- Nh3 production- tissue necrosis
o Attached to epithelium
o Resistant to phagocytosis
• Arcanobacterium/ Corynebacterium pyogenes, E. coli
o Usually ascending and rarely hematogenous route
§ Cystitis, urethritis, pyelitis= nephritis (usually bilateral)
Clinical signs of Contagious bovine pyelonephritis?
Clinical signs
• Subacute course, decreased milk production after calving, fluctuating fever, anorexia, dullness, weight loss,
signs of renal pain, kyphosis, Stranguria, colic
• Abscesses in the kidney upon necroscopy
Contagious bovine pyelonephritis rectal exam lab exam US exam?
Rectal exam
• Painful, enlarged left kidney with abnormal consistency and irregular surface (+/- enlarged ureter)
US exam
• Kidneys, bladder
Lab exam
• Blood
o Anaemia, neutrophilia, uraemia
• Urine
o Macroscopic abnormalities: smell, colour, debris, pus, mucus, free NH3
o pH 8-9
o Detection of protein, blood, neutrophils
o Detection of C. Renale: microscope, IF method, culture
Diagnosis , treatment and prevention and prognosis of Contagious bovine pyelonephritis?
Diagnosis
• History, clinical signs, urinalysis, US, differentiate from RPT, other urinary diseases
Treatment
• AB
o Penicillin + streptomycin
• Acidification 10-14 days
o Sodium phosphate 100g/24 hours
• Nephrectomy
Prevention
- Good hygiene at calving
- Avoid catheterization and breeding with a bull
Prognosis
• Early= favourable
• Later= questionable- poor
Urolithiasis?
Urolithiasis
- Feedlot bulls: in vivo 0-10%, post-mortem 75-80%
- Feedlot lambs: in vivo 12-15%, post-mortem 85-100%
- Occurs between October- march
Uroliths
o Magnesium-ammonium-phosphate (struvite)= most common
o + Ca phosphate, Mg carbonate, Ca carbonate, silica, Ca oxalate
• Stone formation
o Kidney/ bladder
o Accumulation within the bladder
o Urethral obstruction
Pathogenesis of urolithiasis?
Pathogenesis
• Increased grain intake and decreased water intake leading to saturated urine. This alters the pH, the effect
of this influence’s crystal formation and stability of protective colloids.
• There is nidus formation: due to inflammation (adenovirus, bacteria), vitamin A deficiency and oestrogens
(synchronization, clover) there is precipitation of solutes resulting in sand or stone formation.
• Consequences
o Hydronephrosis, pyelitis, cystitis, urethral obstruction, bladder rupture
Clinical signs of urolithiasis?
Clinical signs
- May be silent or can occur with abdominal pain
- Signs of cystitis (several animals affected)
- Signs of urethral obstruction
o Sudden colic, dysuria, Stranguria, haematuria, crystals on preputium, signs of urethral dilatation in
bulls at the perineum
• Rupture of the urethra
o Infiltration with urine
§ Abdomen, perineum= uraemia= death
• Rupture of the bladder
o Uroperitoneum= uraemia +/- undulation, abdominocentesis= death
