Pulmonary strongyloidiasis: an unusual opportunistic pneumonia in a patient with AIDS

Strongyloides Stercoralis Infection Among Human Immunodeficiency Virus (HIV)-Infected Patients in the United States of America: A Case Report and Review of Literature

Patient: Male, 61

Final Diagnosis: Strongyloides stercolaris-associated diarrhea

Symptoms: Diarrhea • epigastric pain • nausea • weight loss

Medication: Ivermectin

Clinical Procedure: Colonic biopsies

Specialty: Infectious Diseases

Strongyloides hyperinfection syndrome and VRE pneumonia

Immunocompromised patients have high risk of infections from bacteria, viruses, fungi and parasites. One of these infections is those caused by Strongyloides stercoralis Immunocompromised patients are at risk of hyperinfection syndrome which is characterised with more systemic manifestation and a higher risk of morbidity and mortality. This can be complicated by coinfection with enteric organisms, specifically Gram-negative. Enterococci are Gram-positive cocci which are inhabitants of the human gastrointestinal tract. Even though enterococci can cause serious infections in multiple sites, they are a rare cause of pneumonia. We present a case of disseminated strongyloides with vancomycin-resistant enterococcus causing pneumonia. The patient had a complicated course with respiratory failure and septic shock. He died eventually due to his severe infections. After a literature review, we could not find a similar case of coinfection of disseminated strongyloides with vancomycin-resistant enterococcus pneumonia in immune-compromised patients.

Eosinophilic pneumonias

This review starts with discussions of several infectious causes of eosinophilic pneumonia, which are almost exclusively parasitic in nature. Pulmonary infections due specifically to Ascaris, hookworms, Strongyloides, Paragonimus, filariasis, and Toxocara are considered in detail. The discussion then moves to noninfectious causes of eosinophilic pulmonary infiltration, including allergic sensitization to Aspergillus, acute and chronic eosinophilic pneumonias, Churg-Strauss syndrome, hypereosinophilic syndromes, and pulmonary eosinophilia due to exposure to specific medications or toxins.

Dissemination of Strongyloides stercoralis in a patient with systemic lupus erythematosus after initiation of albendazole: a case report

Introduction

Strongyloides stercoralis infection affects hundreds of millions of people worldwide. As immigration rates and international travel increase, so does the number of cases of strongyloidiasis in the United States. Although described both in immigrant and in immunosuppressed populations, hyperinfection and dissemination of S. stercoralis following the initiation of antiparasitic medication is a previously unreported phenomenon.

Case presentation

Here we describe the case of a 38-year-old immunocompromised woman with systemic lupus erythematosus, who developed disseminated disease following treatment with albendazole (400 mg every 12 hours). Notably the patient was receiving oral prednisone (10 mg once daily), azathioprine (50 mg twice daily), and hydroxychloroquine (400 mg daily) at the time of hospitalization. The patient was subsequently treated successfully with ivermectin (200 mcg/kg daily).

Conclusion

The reader should be aware that dissemination of S. stercoralis can occur even after the initiation of antiparasitic medication.

Imaging of Parasitic Diseases of the Thorax

A broad spectrum of parasitic infections frequently affects the lungs, mediastinum, and thoracic wall, manifesting with abnormal imaging findings that often make diagnosis challenging. Although most of these infections result in nonspecific abnormalities, familiarity with their imaging features and the diagnostic pathways help the radiologist to formulate an adequate differential diagnosis and to guide diagnosticians in reaching a definitive diagnosis.

[Disseminated strongyloidiasis associated with pulmonary fibrosis and gastrointestinal bleeding]

Strongyloidiasis is a parasitic disease that can be lethal in immunosuppressed patients especially if lung fibrosis is associated, which has been rarely reported. We report the case of a patient treated with corticosteroids for pulmonary fibrosis who developed disseminated strongyloidiasis revealed by massive gastrointestinal bleeding. Diagnosis was based on histological analysis of gastrointestinal biopsies and broncho-alveolar lavage. Treatment improved digestive features as well as respiratory function.

Intestinal strongyloidiasis: recognition, management, and determinants of outcome

Significant advances have occurred in our understanding of the biology, immunology, and immunopathology of the usually asymptomatic human infection by the intestinal parasite, Strongyloides stercoralis. Factors that increase the risk for the occurrence of symptomatic intestinal hyperinfection and/or often-fatal disseminated strongyloidiasis have been better defined. The pathophysiology underlying these risk factors, whether disease-related or iatrogenically induced, is a compromised immune system leading to dysfunction of TH-2 helper cells. These specialized lymphocytes are central to maintaining the delicate balance that exists between the infected human host and the stabilized parasite. Recognition of risk factors that impair the function of TH-2 lymphocytes is essential to heightening the index of clinical suspicion enhancing earlier, accurate diagnosis, and the introduction of appropriate therapy. This review summarizes what is understood about infection by S. stercoralis; its focus will be on the epidemiology, diagnosis, clinical presentation patterns in the immunocompetent and immunocompromised human hosts, and recommended treatment regimens.

Thoracic Manifestations of Tropical Parasitic Infections: A Pictorial Review

Parasitic infections are distributed worldwide and affect hundreds of millions of individuals-primarily those living in endemic areas or in regions with a high rate of immigration from endemic areas-causing significant morbidity and mortality. A broad spectrum of parasitic infections (eg, amebiasis, malaria, trypanosomiasis, ascariasis, strongyloidiasis, dirofilariasis, cystic echinococcosis, schistosomiasis, paragonimiasis) frequently affect the lungs, mediastinum, and thoracic wall, manifesting with abnormal imaging findings that often make diagnosis challenging. Although most of these infections result in nonspecific abnormalities, familiarity with their imaging features as well as their epidemiologic, clinical, and physiopathologic characteristics may be helpful to the radiologist in formulating an adequate differential diagnosis.

Pulmonary Strongyloidiasis: The Varied Clinical Presentations

Strongyloides stercoralis is a unique parasite. It can complete its life cycle entirely within the human host. As a result, an autoinfection cycle is set up. As long as there is an intact immune system, the host can control the parasitic burden, and the organism may persist for years after the initial inoculum. Most infected individuals experience mild gastrointestinal or pulmonary symptoms that may fluctuate for years. When cell-mediated immunity becomes impaired (ie, corticosteroid use, malignancy, acquired immunodeficiency syndrome), the parasite burden will grow, disseminate, and cause hyperinfection. Strongyloidiasis is endemic in the tropical and subtropical areas of the world; additionally, it is also endemic in the southeastern United States. Strongyloidiasis is associated with asthma, preexisting lung disease, and immunosuppression, including acquired immunodeficiency syndrome. Eosinophilia is not a prerequisite; therefore, the diagnosis of strongyloidiasis requires a high index of suspicion.

Viruses and other miscellaneous organisms

Pulmonary infections caused by several types of viruses and other miscellaneous organisms may cause disease in HIV infection. Evidence suggests that pulmonary conditions may result from infections of the lung by HIV itself. Other viruses, most commonly cytomegalovirus, may be primary perpetrators of pneumonitis or may contribute to diseases caused by coexisting infections. Although diagnosis and assessment of the clinical significance of these infections may be difficult, their recognition is of practical importance because potentially effective therapeutic agents are available for several of them. Miscellaneous infections such as pulmonary toxoplasmosis and pertussis are other uncommon but potentially treatable complications of HIV disease.

Strongyloides stercoralis eosinophilic granulomatous enterocolitis

Six patients suffering from an unusual form of colitis produced by Strongyloides stercoralis hyperinfection are described. In contrast to the usual Strongyloides hyperinfection syndrome, in which small intestinal and pulmonary manifestations are seen in patients with some forms of immunodeficiency, the patients described here presented with only a characteristic transmural eosinophilic granulomatous inflammation affecting mostly the colonic wall and clinically mimicking ulcerative colitis or Crohn's disease. This Strongyloides eosinophilic granulomatous enterocolitis apparently results from a florid inflammatory response by eosinophils, histiocytes, and giant cells with formation of granulomas that destroy the larvae entering the colon. This morphologic picture differs from that of the well-described hyperinfection syndrome, in which the bulk of the larvae pass through the colonic wall to complete the life cycle, with only a few larvae destroyed in the colon. The probable pathophysiologic mechanism of this unusual manifestation of hyperinfection is discussed based on the anatomic and clinical observations of patients who presented at different stages in the evolution of their condition and whose length of follow-up varied.