INTRODUCTION: Stongyloides Stercoralis is an enteric nematode that usually causes asymptomatic eosinophilia in immunocompetent hosts and can persist in the body for long periods. It can, however, cause fatal infections in immunocompromised hosts. It has been rarely reported as a cause of COPD exacerbation, as well as of interlobular fibrosis. We report a patient with chronic intermittent gastrointestinal symptoms and recurrent COPD exacerbations along with CT scan of chest showing pulmonary infiltrates and ground glass opacities. After extensive workup, the patient was found to have S. Stercoralis infection and showed significant improvement of pulmonary and gastrointestinal symptoms after treatment with Ivermectin.
CASE PRESENTATION: A 62 year old Caucasian male with a known history of COPD presented with dyspnea, wheezing and abdominal pain for a few days. The patient reported episodic abdominal pain, vomiting and diarrhea intermittently for six months. During that time period, he was hospitalized several times for acute COPD exacerbations. Previous work up included routine blood work, peripheral eosinophil count of 7100, negative sputum and stool cultures and spirogram revealing airflow obstruction with FEV1 53% predicted. Bronchoscopy was unremarkable with a non-diagnostic BAL. Transbronchial biopsy demonstrated non-specific inflammatory changes. Endoscopic biopsies demonstrated evidence of eosinophilic infiltration in the gastric mucosa. For a presumptive diagnosis of hypereosinophilic syndrome, the patient was then treated with Prednisone with only partial improvement. On this admission, repeat spirogram showed FEV1 of 37% predicted. CT scan of abdomen was unremarkable. CT scan of chest showed bilateral pulmonary infiltrates with air space and ground glass opacities. Antibiotics and corticosteroids yielded little improvement. The patient was then tested for S. Stercoralis by serum antibody titer and stool culture, which were positive. Upon further questioning, we found he had been a surveyor in Louisiana for a few years. Treatment with Ivermectin resulted in significant improvement in both pulmonary and gastrointestinal symptoms. He continued to feel well without any re-admissions for COPD exacerbations during the following six months.
DISCUSSION: S. Stercoralis is an intestinal parasite predominantly found in tropical and subtropical areas (e.g. southeastern United States). The primary mode of transmission occurs when larvae from contaminated feces penetrate the skin. Immunocompetent hosts remain asymptomatic (with peripheral eosinophilia), even for years, while immunosuppressed can develop disseminated strongyloidiasis or hyperinfection syndrome, both considered systemic strongyloidiasis(1). Disseminated strongyloidiasis occurs when the organism, in the larval form, is found outside the usual migration pattern. Hyperinfection is an augmentation of the life cycle, resulting in a heavy infestation of worms in the lungs(1) . Patients with COPD, who are infected by this organism and have altered cellular immunity or on therapy with corticosteroids, could develop hyperinfection and dissemination of the larvae from the gastrointestinal tract to the bloodstream (2). In such context there should be search for rhabditiform larvae in stool. It is not routinely tested and has to be requested separately. It is important to consider Strongyloidaisis since it is an easily treatable condition, which if left untreated can be fatal. If intestinal infection with S. Stercoralis is suspected, detected, and treated before immunosuppressive therapy is initiated, morbidity and mortality from the disease can be prevented.
CONCLUSIONS: The unexpected presence of enteric symptoms in the context of recurrent COPD exacerbation with unexplained chronic eosinophilia should prompt investigation for S. Stercoralis, which if treated early, can prevent further morbidity
Reference #1 Keiser PB, Nutman TB Strongyloides Stercoralis in imunocompromised population. Clin Microbiol Rev. 2004;17(1):208
Reference #2 Sen P, Gil C, Estrellas B, Middleton JR. Corticosteroid-induced asthma: a manifestation of limited hyperinfection syndrome due to Strongyloides stercoralis. South Med J. 1995;88(9):923
DISCLOSURE: The following authors have nothing to disclose: Mohammad Syed, Swapna Devanna, Muhammad Siddique, Patricia Hopkins-Price, Haitham Bakir
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