AIDS affects each of the major organs in the genitourinary system and the predominant causitive agent HIV-1 has been cultured from body fluids including blood, urine, pre-ejaculate and vaginal secretions.

Thirty percent of AIDS patients develop significant proteinuria, 50% have pyuria, 18% have haematuria and 50% are hypogonadal. Voiding dysfunction with urinary retention may result from an inflammatory, infectious or neurologic cause. Furthermore, weight loss, malnutrition and side effects of medication may impact on the genitourinary system.

The incubation period for development of AIDS following HIV infection differs in different populations - around 10 years for homosexuals and haemophiliacs, and about 5 years for blood transfusion.

Functional:

Hyponatraemia
This affects 60% of hospitalised patients. Volume depletion comes from vomiting and chronic diarrhoea. SIADH is associated with PCP, toxoplasmosis and TB.

Hypokalaemia
GI fluid loss. Renal insufficiency due to renal parenchymal disease.

Acid-base disturbances
Opportunistic infections in the lung (respiratory alkalosis to respiratory acidosis)

ARF
Diagnosed in 20-40% of HIV patients.

Structural:

Opportunistic infections
CMV, Cryptococcus, Histoplasma, Candida, Aspergillosis and Mycobacteria.

Tumours
Kaposi's sarcoma and lymphoma.

Nephropathy
HIVN is more common in blacks and men. Most end in ESRD. Peritoneal dialysis is the treatment of choice.

Aids affects both the peripheral and central nervous systems. Toxoplasmosis is the most common opportunistic infection and affects up to 15% of AIDS cases with neurologic disease. AUR is the most common presenting feature. Urodynamic evaluation reveals areflexia, hyperreflexia or hyporeflexia.

Voiding dysfunction is often exacerbated by HIV subacute encephalitis leading to dementia. Patients with AUR secondary to neurologic disease tend to remain in retention. After establishing the diagnosis with neurological examination and urodynamics, CISC is the treatment of choice, or SPC if the patient is unable to self catheterise.

Infection with CMV and toxoplasmosis have been reported. Involvement of the bladder with KS or NH lymphoma can result in enterovesical fistulae formation and should be excluded in patients with recurrent UTI's or pneumaturia.

This is the site of numerous opportunistic infections in AIDS patients. Patients usually present with fever, voiding symptoms and a UTI. Examination usually reveals a tender prostate +/- fluctuance due to abscess. Common bacteria are E. coli, H. influenzae, Klebsiella, M. avium, M. tuberculosis, Pseudomonas, Salmonella and Staph. Aureus. Funghi include Cryptococcus and Histoplasma and viruses include Cytomegalovirus and HIV.

The incidence of prostatitis is increased in the HIV infected patients with an increased risk of abscess formation. Transurethral drainage with intra-operative cultures for aerobes, anaerobes, funghi and mycobacteria.

There is a reported increased progression rate for carcinoma of the prostate. Patients are often hypogonadal and do not respond readily to hormone manipulation.

Kaposi's sarcoma is one of the earliest manifestations of HIV disease and is the commonest malignancy associated with AIDS. Clinically, KS is manifested by nodules, plaques LN involvement, lymphoedema and visceral involvement. Twenty percent of KS have genital lesions. Penile KS presents as a purplish-red lesion. Solitary lesions can be treated with local excision or fulguration. Larger multifocal lesions often require DXT. Periurethral lesions can obstruct the urethra and urethral dilatations or SPC may be required.

Frequency/dysuria is secondary to CMV, metabolite induced damage or HIV activation. Reiter's syndrome is associated with AIDS. HIV testing should be recommended in new patients with RS who have risk factors for HIV. Primary T and B cell lymphomas of the urethra have also been reported.

Testicular atrophy from a prolonged febrile state, testicular infection and secondary dysfunction from hypothalamic-pituitary disease. Opportunistic infections include CMV, Candida and toxoplasmosis.

There is a 0.2% (50 times that of normal population) incidence of germ cell and non germ cell tumours. Asymptomatic HIV patients should receive standard treatment, but there are problems with AIDS patients tolerating chemotherapy and surgery.

Obstructive epididymitis is secondary to CMV inclusion bodies and KS cells. Opportunistic infections include salmonella which is difficult to eradicate and may need lifelong maintenance therapy.

Fournier's gangrene - often atypical causative pathogens.

There is an increased incidence in AIDS patients caused by primary and secondary gonadal failure, dementia and peripheral neuropathy. Testosterone injections have been shown to reduce the incidence.