Efficacy of highly active antiretroviral therapy in HIV‐infected, institutionalized orphaned children in Tanzania

Previous conclusions concerning pulmonary function in non-atopic and atopic asthma in childhood appear to differ depending on whether the cohorts studied are drawn from the community or clinic. In studies on community-based cohorts, Kelley et al. (1) found no differences in asthma severity and pulmonary function and Kurukulaaratchy et al. (2) found that baseline spirometric parameters (FEV1, FVC or PEF) were not significantly different when comparing nonatopic and atopic children with asthma. In contrast, Ostergaard (3) who identified 84 cases from an allergy clinic found that non-atopic asthmatics had significantly more hyperinflation, reduced pulmonary function and more hospital admissions than atopic asthmatics. These observations raise questions as to whether non-atopic asthma presenting to specialist clinics differs from that detected in the community and whether it differs qualitatively from atopic asthma. In this study we compare pulmonary function in children with non-atopic and atopic asthma presenting to a tertiary hospital specialist clinic. A retrospective case–control design in patients drawn from a specialist paediatric respiratory clinic was used. Asthma diagnosis was made by a paediatric respiratory physician. Allergen Skin Prick Tests (SPTs) and Pulmonary Function Tests (PFTs) were performed in the respiratory laboratory between 1996 and 2006 and methodologies for their performance did not change during this period. We selected 53 children with a diagnosis of asthma, who were non-atopic on SPTs and had had PFTs and age (±6 months) and gender matched with 53 children with a diagnosis of asthma who were atopic on SPTs and had had PFTs. The PFTs used for the analysis were those performed at the same time as the SPTs in over 90% of the patients. PFTs were performed using standardized spirometric techniques (4) with a Vmax Spirometer (Sensormedics 6200, Yorba Linda, CA) and baseline forced vital capacity (FVC), forced expiratory volume (FEV1), forced expiratory flow between 25% and 75% vital capacity (FEF 25–75) and peak expiratory flow (PEF) recorded as a percentage predicted (5). The FEV1/FVC ratio was also calculated. SPTs were performed on nine inhalant allergens extracts: grass mix, rye grass, English plantain, cat pelt, dog hair, two house dust mite (HDM) species (Dermatophagoides pteronyssinus, Dermatophagoides farinae), cockroach mix and Alternaria (Hollister Stier, Spokane, WA, USA) as well as positive (histamine 10 mg/ml) and negative (saline) controls. Atopic subjects were defined as those who had at least one positive reaction with a mean wheal diameter measuring 3 mm or more or 3 mm greater than a wheal obtained with a negative control. Clinical information was obtained from the subjects’ medical record after matching of atopic with non-atopic subjects was complete. The study was approved as a medical record audit by the hospital’s ethics committee. Chi-square and independent sample t-tests were determined using SPSS 11.5. A p-value of 0.05 or less was regarded as significant. We matched age and sex of 53 non-atopic asthmatic children (median age 6.28 years, 58.5% male) with 53 children with atopic asthma (median age 6.85 years, 58.5% male). Height (mean 126.79 cm vs. 124.58 cm), weight (median 25.65 kg vs. 25.14 kg) and BMI (median 16.84 vs. 16.53) also did not differ significantly in children with non-atopic and atopic asthma. The 53 atopic children were positive to the following allergens: HDM (92.5%), Alternaria (32.1%), cockroach (28.3%), cat (26.4%), rye grass (24.5%), grass mix (18.9%), plantain (15.1%) and dog (7.5%). Children with non-atopic asthma had a higher prevalence of documented bronchiolitis in infancy (13/53 vs. 4/53; p = 0.017), were more likely to present initially with cough in the absence of wheeze (16/47 vs. 8/46; p = 0.049) and were less likely to have a history of atopic dermatitis ever (17/38 vs. 34/47; p = 0.01). There was no difference between the age of onset of asthma symptoms between the non-atopic and atopic group with 26 of 45 (58%) of the non-atopic group and 23 of 43 (54%) of the atopic group developing symptoms in the first 3 years of life. There was no difference in inhaled corticosteroid (ICS) use at the time of presentation to the clinic, but the non-atopic group was less likely to be treated in the ICS by the respiratory physician (27/52 vs. 40/53; p = 0.013). Overall, there were no significant differences for any of the