Introduction

• Inflammation of the bladder.
• Causes: usually an ascending bacterial infection; predisposing factors are necessary for this opportunistic infection. Rarer causes include cyclophosphamide toxicity, eosinophilic cystitis, polypoid cystitis, foreign bodies. 
• Signs: stranguria, dysuria, increased frequency of urination (pollakiuria) and small amounts of urine, hematuria, abnormal smell/turbidity of the urine, more rarely abdominal discomfort, excessive licking, attracting male dogs.
• Treatment: antibiotics, pain killers.
• Sequelae: ascending urinary tract infections (pyelonephritis), diskospondylitis (rarely), prostatitis, sepsis, endocarditis, urolithiasis.
• Prognosis: good if uncomplicated; guarded if chronic; poor if secondary to malignant neoplasia.

Pathogenesis

Etiology

• Bacterial infection (often E. coli Escherichia coli, Staphylococcus Staphylococcus spp, Streptococcus Streptococcus spp, Klebsiella Klebsiella pneumoniae, Proteus Proteus spp ).
• Fungal infection (rare: Candida spp Candida albicans). 
• Toxicity: cyclophosphamide Cyclophosphamide. 

Predisposing factors

Causes of lower urinary tract infection and/or inflammation

• Trauma Bladder: trauma rupture (iatrogenic - catheterization).
• Glucocorticosteroids (iatrogenic, hyperadrenocorticism Hyperadrenocorticism ), other immunosuppressive drugs (eg cyclosporine Ciclosporin). 
• Glucosuria (diabetes mellitus Diabetes mellitus , Fanconi's syndrome Fanconi's syndrome ).

• Bladder diverticulum Bladder: diverticulum, ectopic ureters Ureter: ectopic, especially with ureteroceles, excessive perivulvar skin folds.
• Decreased urine concentration (polyuria).
• Indwelling urinary catheters.
• Urolithiasis Urolithiasis.
• Drugs (chemotherapeutic agents, eg cyclophosphamide Cyclophosphamide ).

• Bladder distension (neurological or polyuria) increases binding sites for bacteria and reduces blood flow in bladder wall.
• Decreased urethral function.

Pathophysiology

• It is usually an ascending bacterial infection, less likely a hematogenous infection.
• Predisposing factors + opportunistic microbes → ascending into bladder → cystitis → pyelonephritis Kidney: pyelonephritis, diskospondylitis Diskospondylitis, struvite urolithiasis Urolithiasis, prostatitis Acute prostatitis, septicemia Shock: septic.

Timecourse

• Days to weeks.

Diagnosis

Treatment

Prevention

Outcomes