Pulmonary vascular disease in Africa: Lessons from registries

Abstract

The epidemiology of pulmonary vascular disease (PVD) remains unclear in Africa, where health systems do not reach the majority of the population and heath information systems are poorly developed. In this context, registries are particularly important in gathering crucial information on PVD, aiming at improving knowledge of the epidemiology and/or quality of care. While population-based registries are the main tool to identify incident cases, and be a better indicator of pulmonary vascular disease burden, hospital-based registries can give an indication of the demand for specific care services, which is useful for health policy and planning. The only registry for pulmonary hypertension in Africa - the Pan African Pulmonary Hypertension Cohort (PAPUCO) - involved four countries, and was a pragmatic study that revealed a unique pattern of environmental risks, issues related to low access to health care, and ill-equipped health facilities for diagnosis and management of pulmonary hypertension. In addition, disease specific registries for conditions such as congenital heart disease and rheumatic heart disease uncovered high occurrence of PVD that can be managed and/or prevented with improvements in community awareness, surveillance, management and prevention. It is suggested that existing networks of experts and researchers develop regional registries to determine the epidemiology of PVD in Africa, assess geographic, environmental and seasonal differentials, as well as inform policy and care provision in the continent.

Figure 1.. Chest X-ray of a 7-years old girl with perinatal HIV infection, followed by recurrent pulmonary tuberculosis and persistent high viral load associated with poor adherence to therapy for both HIV and tuberculosis.

The image shows apical pleural thickening and cardiac silhoute not well defined due to heterogeneous opacities and centrilobular nodular pattern affecting the right medial and basal middle lobe, due to possible transbronchial dissemination from the left lung to the middle lobe of the right lung, suggesting a re-activation of tuberculosis. Left lung “destroyed” as a result of tuberculosis, in the upper lobe there are areas of emphysema and fibrosis, as well as consolidation of the lower lobe with cavitation (cavernous aspect) and bronchiectasis.

Figure 2.. Left ventricle anfractuous surface (upper left, arrow) in an area that corresponds to the basis of a thrombus previously detached to the aorta (upper right).

Hematoxylin-Eosin 100x right ventricular endomyocardial sample revealing marked hyaline thickness of endocardium, scarce cellularity and large fibrosis bands into the myocardium (lower left). Eosinophilic granulomas centered by viable Schistossoma eggs (lower right, arrow) in a sample of the urinary bladder.

Figure 3.. Countries participating in the multinational registries in Africa that assessed the occurrence of pulmonary vascular disease.

PAPUCO is, to date, the only all Africa disease specific registry for pulmonary hypertension, while REMEDY and VALVAFRIC were both for rheumatic heart disease, with the latter involving exclusively African countries.