Schistosomiasis‐Associated Pulmonary Hypertension

Abstract

Schistosomiasis, a parasite-borne disease, is highly prevalent in Africa and Asia; it is estimated that close to 20 million people worldwide have a severe form of the disease. The chronic form can affect the gastrointestinal system and lead to hepatosplenic disease, and it may cause cardiopulmonary complications, including pulmonary hypertension. The exact pathogenesis of schistosomiasis-associated pulmonary hypertension (Sch-PH) remains unclear, although several mechanisms, including parasitic arterial embolization, pulmonary arteriopathy, and portopulmonary hypertension-like pathophysiology, have been suggested. The immunopathology of the disease is also unclear, although there are similarities with the immunology of idiopathic pulmonary arterial hypertension (PAH). Finally, the treatment of Sch-PH has not been well studied. There is some evidence on treating the underlying infection, with unclear effect on Sch-PH, and advanced PAH therapies are now being suggested, but more studies are needed to confirm their efficacy.

Pulmonary nodules in African migrants caused by chronic schistosomiasis

“…20 Schistosomiasis-induced pulmonary hypertension is common in areas of high endemicity, 2 with prevalence estimated at 8-25%. 21 Gonçalves and colleagues, 24 in their series of 1863 consecutive autopsies in Belo Horizonte, Brazil, reported 313 (16·8%) cases of S mansoni infection, with eggs found in almost all organs. Eggs were also found in the lungs of 93 (29·7%) of 313 cases with schistosomiasis.…”

“…Chronic intestinal schistosomiasis, defi ned as the presence of parasites in stool without portal hypertension, and chronic hepatosplenic schistosomiasis, defi ned as the presence of parasites in stool with portal hypertension and periportal fi brosis, are mainly caused by S mansoni and S japonicum. 21 The latter has also been associated with dwarfi sm and granulomatous disease of the large intestine (colonic tumoroid proliferation) in the advanced stage of the disease. 22 The involvement of the lungs in the chronic phase is usually described in relation to pulmonary hypertension.…”

“…21 Pulmonary hypertension might result from all these mechanisms, and each mechanism could be prominent in diff erent stages of the infection. This hypothesis could also explain the distribution of the schistosome-induced pulmonary hypertension in two main age groups: young patients (with high burden of recent infection causing massive egg embolisation), and the elderly individuals (for whom the immune-mediated infl am matory cascade and the portal hypertension might have a major role).…”

“…This hypothesis could also explain the distribution of the schistosome-induced pulmonary hypertension in two main age groups: young patients (with high burden of recent infection causing massive egg embolisation), and the elderly individuals (for whom the immune-mediated infl am matory cascade and the portal hypertension might have a major role). 21 The clinical presentation of chronic pulmonary schistosomiasis can be divided into three main categories: asymptomatic cases with eggs in the pulmonary beds, with or without granuloma formation; granuloma formation with pulmonary hypertension; and granuloma formation with pulmonary hypertension and cor pulmonale. 20,23 Patients who progress to cor pulmonale present signs and symptoms that are analogous to those presented by patients with pulmonary hypertension and cor pulmonale due to other causes.…”

Schistosomiasis and pulmonary hypertension

“…Hastalığa Schistosoma denilen parazitik trematod neden olur. Şistosomiyazis dünya genelinde malarya ve amebiyazisten sonra en sık görülen üçüncü paraziter hastalıktır (1,2). Akut ve kronik hastalık olarak karşımıza çıkabilir.…”