| Popis: |
Background Community-acquired pneumonia (CAP) is one of the commonest causes of adult hospitalisation in sub-Saharan Africa, but recent data describing its epidemiology, microbial aetiology and outcome are limited. Focusing particularly on Malawi, the overall aim of this thesis was to describe the aetiology and outcome of CAP in sub-Saharan African to determine the key predictors of mortality. Methods Firstly, a systematic review of studies of CAP in adults in sub-Saharan Africa was performed to describe CAP aetiology, estimate the mortality rate and identify risk factors associated with death. Secondly, a prospective observational study of adults hospitalised with clinically diagnosed CAP to Queen Elizabeth Central Hospital, Blantyre, Malawi was completed to describe microbial aetiology using modern diagnostic modalities, determine outcome and identify prognostics factors. Thirdly, having identified in preliminary analyses of the prospective cohort that hypoxaemia was an independent risk factor for mortality, a study of the effectiveness of supplemental oxygen delivery by oxygen concentrator to correct hypoxaemia in adults with suspected CAP was performed. Results In both the systematic review and the prospective cohort the predominant burden of hospitalised CAP was in young (average age 38 and 35, respectively) and HIV-positive (52% and 78%) patients with limited chronic cardiovascular and pulmonary comorbidity. Streptococcus pneumoniae (27% and 21%) and Mycobacterium tuberculosis (19% and 23%) were the most commonly identified causes. The overall mortality rate for hospitalised patients in the systematic review was 9.5%, but data describing prognostic factors were limited. In the prospective cohort (n=459), death by day 30 occurred in 14.6% and was associated with: male sex (aOR 2.57); pre-presentation symptom duration (aOR 1.11 per day increase); inability to stand (aOR 4.28); heart rate (aOR 1.02 per beat/minute rise); oxygen saturations (aOR 0.95 per % rise); white cell count (aOR 0.91 per 109/L rise); haemoglobin (aOR 0.90 per g/dL rise). A newly derived four parameter mortality risk prediction tool based on male sex, oxygen saturations |
