Pulmonary strongyloidiasis: assessment between manifestation and radiological findings in 16 severe strongyloidiasis cases

Abstract

BackgroundStrongyloidiasis is a chronic parasitic infection caused by Strongyloides stercoralis. Severe cases such as, hyperinfection syndrome (HS) and disseminated strongyloidiasis (DS), can involve pulmonary manifestations. These manifestations frequently aid the diagnosis of strongyloidiasis. Here, we present the pulmonary manifestations and radiological findings of severe strongyloidiasis.MethodsFrom January 2004 to December 2014, all patients diagnosed with severe strongyloidiasis at the University of the Ryukyus Hospital or affiliated hospitals in Okinawa, Japan, were included in this retrospective study. All diagnoses were confirmed by the microscopic or histopathological identification of larvae. Severe strongyloidiasis was defined by the presence of any of the following: 1) the identification of S. stercoralis from extra gastrointestinal specimens, 2) sepsis, 3) meningitis, 4) acute respiratory failure, or 5) respiratory tract hemorrhage. Patients were assigned to either HS or DS. Medical records were further reviewed to extract related clinical features and radiological findings.ResultsSixteen severe strongyloidiasis cases were included. Of those, fifteen cases had pulmonary manifestations, eight had acute respiratory distress syndrome (ARDS) (53%), seven had enteric bacterial pneumonia (46%) and five had pulmonary hemorrhage (33%). Acute respiratory failure was a common indicator for pulmonary manifestation (87%). Chest X-ray findings frequently showed diffuse shadows (71%). Additionally, ileum gas was detected for ten of the sixteen cases in the upper abdomen during assessment with chest X-ray. While, chest CT findings frequently showed ground-glass opacity (GGO) in 89% of patients. Interlobular septal thickening was also frequently shown (67%), always accompanying GGO in upper lobes.ConclusionsIn summary, our study described HS/DS cases with pulmonary manifestations including, ARDS, bacterial pneumonia and pulmonary hemorrhage. Chest X-ray findings in HS/DS cases frequently showed diffuse shadows, and the combination of GGO and interlobular septal thickening in chest CT was common in HS/DS, regardless of accompanying pulmonary manifestations. This CT finding suggests alveolar hemorrhage could be used as a potential marker indicating the transition from latent to symptomatic state. Respiratory specimens are especially useful for detecting larvae in cases of HS/DS.

Acute Respiratory Distress Syndrome With Alveolar Hemorrhage due to Strongyloidiasis Hyperinfection in an Older Patient

“…9) Strongyloidiasis with acute respiratory failure and pulmonary hemorrhage is rare and almost is accompanied by an immunodeficiency disease. 5,6,8,12) In the present case, there was no definite underlying disease, but there was a history of intra-articular corticosteroid injection and old age. This is significant because Strongyloides hyperinfection may be associated with coinfection with CMV, P. jirovecii, and Aspergillus spp.…”

“…Therefore, autoinfection can lead to hyperinfection, resulting in the development of complications involving the gastrointestinal tract, lungs, and peritoneum. 7,8) Hyperinfection risk factors include decreased cellular immunity, age ≥65 years, chronic lung diseases, intestinal blind loops, achlorhydria, and the use of corticosteroids, antacids, or H2 blockers. 3,9) The use of corticosteroids was the main triggering factor that induced hyperinfection, but the cumulative dose or duration of the corticosteroid treatment causing Strongyloides hyperinfection was not known.…”

Morphological variation of four species of Strongyloides (Nematoda, Rhabditida) parasitising various mammal species

“…People parasitized by this species of helminth have nocturnal dyspnea, sweatiness, productive cough, and also constrictive pericarditis (Lee et al, 2017). The study by Nabeya et al (2017) described cases of manifestations in the lungs, including acute respiratory distress syndrome, bacterial pneumonia and lung bleeding.…”

Pulmonary Diseases in Refugees and Migrants in Europe

“…Patients with severe strongyloidiasis can therefore develop acute respiratory distress syndrome and pulmonary hemorrhages, together with bacteremia due to intestinal translocation. Chest X-rays frequently show diffuse shadowing [97], and mortality can be as high as 60% [96]. Usually, as far as this syndrome is considered, the diagnosis is rather easy because worms can be found in all fluids and secretions (including sputum and bronchoalveolar lavage).…”