Lung disease common in adolescents with HIV in Zimbabwe

Healthcare workers treating older children and adolescents with HIV in sub-Saharan Africa should be alert for early symptoms of chronic lung disease in their patients, and do their best to identify and treat HIV infection before it has a significant impact on those who survive beyond the first year of life.

The lung disease, which is not related to tuberculosis, is severely debilitating.

Without antiretroviral treatment around two-thirds of infants perinatally infected with HIV will die before reaching the age of one year, but evidence from southern Africa shows that, among the remainder, survival into adolescence is common. 

Twenty-eight per cent of infants infected with HIV around the time of birth or during breastfeeding will survive to the age of ten, and those who survive the first year of life have a median survival of 16 years.

Among this group of survivors, late presentation with HIV disease is common. Children often show severe stunting, delayed puberty and severe cutaneous problems before developing opportunistic infections.

“Although the number of younger children with HIV in our hospitals is melting away due to antiretroviral therapy, the number of older children we are seeing is growing,” said Dr Rashida Ferrand, presenting findings from a study conducted in Zimbabwe to the 41st Union World Conference on Lung Health.

A large proportion of older children and adolescents presenting for care to health services in Zimbabwe are infected with HIV, Dr Ferrand told the conference. Among adolescents receiving care at hospitals in Zimbabwe HIV prevalence of 28% has been recorded, while 17% of 10 to 18 year olds attending primary care were HIV-positive in one cross-sectional study.

A survey of all children enrolled in the first year of primary education in one district of Zimbabwe found an HIV prevalence of 2.8%.

In a country like Zimbabwe with a population of 12 million and high HIV prevalence this means there could be around 30,000 older children and adolescents with undiagnosed HIV infection.

But Dr Ferrand said that among patients of this age group in Zimbabwe, one of the most common problems was chronic and progressive lung disease that frequently leaves patients almost unable to function normally.

She carried out a study in order to understand why so many adolescents without significant evidence of lung damage on chest X-ray were so debilitated, using CT scans to look in more detail at their lungs.

She presented results of a cross-sectional survey of 116 consecutive older children and adolescents with HIV presenting for care at two HIV clinics in Zimbabwe. The mean age was 14, and 69% were receiving antiretroviral therapy; the mean CD4 count was 380.

Among these patients 66% had chronic cough, 21% had a restricted ability to exercise as a result of reduced lung function (NYHA scale 2-4). Forty per cent had hypoxia and 44% had a reduced lung function defined as FEV1 <80% of predicted value. Seven per cent had pulmonary hypertension.

High resolution CAT scan showed that in 50% of patients, there was mosaic attenuation (see link for definition and images), which is strongly correlated with bronchiectasis and airflow obstruction – a condition called obliterative bronchiectasis (OB). It is also characterised by daily production of very large amounts of sputum, coughed up from the airways.

The condition is highly prevalent in Zimbabwean adolescents; a survey showed 44% with CD4 counts above 350 had some evidence of chronic lung disease.

The condition is probably not very responsive to ART, said Dr Ferrand, since there was no significant relationship between the duration of ART exposure and the severity of the condition, suggesting that the condition may be irreversible once established.

Dr Fernand speculated that OB in children with HIV becomes progressive as a result of a cycle of viral and bacterial infections of the respiratory tract, leading to chronic inflammation, small airway damage and an increased risk of mycobacterial infection. Many of the children in the cohort had received multiple courses of presumptive treatment for tuberculosis as a result of their chronic cough.

Dr Fernand said early diagnosis of HIV infection and prompt initiation of HIV treatment appeared to be the best way of preventing development of the condition, but further research was needed to determine the extent to which ART can prevent or relieve the condition. 

Chronic cough in older children should be the trigger for more thorough investigation, said Dr Ferrand, rather than an immediate presumption of TB. “There’s a need to stress that it’s not always TB just because it’s cough and the chest X-ray looks a bit dodgy," she said.

Although CT scans are not available in many countries outside private hospitals, Dr Liz Corbett of the London School of Hygiene and Tropical Medicine told aidsmap: “Once you know what [OB] is, and what to look for, the tests are straightforward.”

“Measuring oxygen saturation is not difficult, and even measuring lung function, although it’s technically challenging, is not a high cost intervention,” said Dr Ferrand.

Very basic complaints about inability to exercise should trigger suspicion. “Being unable to sing because of the coughing is a common sign; it’s a big social handicap in Zimbabwe,” said Dr Corbett.

Dr Ferrand recommended the investigation of aggressive management of intercurrent respiratory infections in children with HIV, together with the use of prophylactic antibiotics. Use of a combination of antiretroviral therapy, bronchodilators and corticosteroids might relieve the condition or prevent progression, but this approach needs to be tested, especially given the risk of predisposing patients to TB by corticosteroid use, she said.

Ferrand R. TB-HIV in adolescents – an emerging challenge. 41^st Union World Conference on Lung Health, Berlin, November 11-15, 2010.