HIV-Associated Wasting Syndrome

HIV wasting syndrome is involuntary loss of over 10 percent of body weight, plus either chronic diarrhoea (two or more loose stools daily for over 30 days) or chronic weakness with documented fever for over 30 days, in the absence of another cause. It is an AIDS defining condition and reflects uncontrolled viraemia, opportunistic infection, malabsorption and metabolic changes.

• Contributors: reduced intake (oral lesions, nausea, depression, food insecurity), malabsorption, hypermetabolism, hypogonadism, chronic inflammation, opportunistic infections, tuberculosis, medications.
• Common in late presentation in Africa, and in children as failure to thrive.

Progressive weight loss with loss of muscle and fat, fatigue, weakness, anorexia, chronic diarrhoea, fever, night sweats.

• Temporal wasting, reduced mid upper arm circumference (under 23 cm in adults), body mass index under 18.5 kg/m2.
• Differential diagnosis: tuberculosis, disseminated Mycobacterium avium complex, lymphoma, Kaposi sarcoma, chronic diarrhoeal infection (cryptosporidiosis, microsporidiosis), cytomegalovirus disease, histoplasmosis, endocrine disease (adrenal insufficiency, thyrotoxicosis, diabetes), depression, malignancy, drug effect.
• Complications: opportunistic infection, poor wound healing, muscle weakness, falls, impaired ART absorption and adherence, higher mortality, pressure injury.

Exclude treatable causes before attributing weight loss to HIV.

• Weight, body mass index, mid upper arm circumference, nutritional screen; CD4 count and viral load.
• Sputum Xpert, chest radiograph, urine lipoarabinomannan, blood cultures for mycobacteria, stool microscopy and culture, cryptococcal antigen, full blood count, glucose, thyroid function, electrolytes, albumin, liver and kidney function, testosterone (men) and morning cortisol.
• Ultrasound abdomen and chest imaging; lymph node aspirate or biopsy; endoscopy or colonoscopy for refractory diarrhoea.

Treat the cause, start antiretroviral therapy and rebuild nutrition.

• Supportive: nutritional rehabilitation with energy 35 to 40 kcal/kg/day and protein 1.5 to 2 g/kg/day, small frequent meals, oral nutritional supplements or ready to use therapeutic food, one 92 g sachet (about 500 kcal) three times daily in severe wasting, multivitamin and zinc, treat oral candidiasis, food security support, resistance exercise, psychosocial support.
• Pharmacological: tenofovir, lamivudine and dolutegravir once daily, start within 2 weeks even with tuberculosis; cotrimoxazole 960 mg daily; treat opportunistic infections by cause; mirtazapine 15 to 30 mg at night for appetite and depression; megestrol acetate 400 to 800 mg daily (watch thromboembolism, adrenal suppression, hypogonadism; avoid in pregnancy); testosterone enanthate 200 mg IM every 2 weeks for men with documented hypogonadism; loperamide 4 mg then 2 mg after each loose stool (maximum 16 mg daily) for non infectious diarrhoea; ondansetron 4 mg for nausea.
• Procedures: nasogastric feeding for severe anorexia or dysphagia; gastrostomy in refractory cases; parenteral nutrition rarely.
• Special groups: children, therapeutic feeding (severe acute malnutrition: F-75 then F-100 or ready to use therapeutic food 200 kcal/kg/day), antiretroviral therapy; pregnancy, nutritional supplementation, avoid megestrol; elderly, assess dysphagia and polypharmacy.
• Red flags: weight loss over 10 percent with fever or cough (tuberculosis), severe diarrhoea with dehydration, hypotension, hypoglycaemia, mental change, refeeding risk with phosphate fall.
• Follow-up: weekly weight in the first month, then monthly; viral load at 3 and 6 months; nutritional review.