check strongyloides for peirpheral eosinophilia before starting high dose steroids

This patient’s travel history, GI symptoms, and eosinophilia make the possibility of helminthic infection quite real, including strongyloidiasis from Strongyloides stercoralis. Since the need to begin immunosuppressive therapy with dexamethasone for this patient’s documented COVID-19 infection is compelling, and patients with chronic strongyloidiasis during immunosuppression can progress rapidly to disseminated helminthic infection, initiation of treatment with ivermectin is recommended while further confirmation of infection is sought.

Strongyloidiasis is endemic to tropical and subtropical regions of the world, including some portions of the United States. Approximately 75% of all infections noted globally occur in Southeast Asia, Africa, and the Western Pacific. The most common route of transmission is via skin contact with contaminated soil. Filariform larvae penetrate the skin and travel via the bloodstream to the alveolar air sacs, from where they ascend the tracheobronchial tree and are swallowed. In the GI tract, the larvae mature into adult worms that reside in the mucosa of the duodenum and jejunum and may live for years. Larvae produced by the adult worms may be passed in the stool or result in a cycle of autoinfection. In patients with diminished cell-mediated immunity, hyperinfection with disseminated disease may develop. Dissemination of larval or adult worms may involve many body sites, including fleeting lung infiltration and gram-negative bacteremia related to increased helminthic involvement of the bowel. With an intact immune system, the chronic stage of strongyloidiasis is most often asymptomatic or characterized by mild GI symptoms. Skin manifestations of migrating larvae are also common.  Eosinophilia is present in a majority of patients during the chronic phase of the illness but often disappears during disseminated disease.

Confirmation of strongyloidiasis is achieved by demonstration of eggs or larvae in the stool, but this test, while specific, is not sensitive. Stool examination should be accompanied by serum testing by enzyme-linked immunosorbent assay for strongyloides antigens. Since stool and serum testing may require several days or longer, patients who require immediate treatment with corticosteroids should be started on an effective anthelmintic, pending test results. Ivermectin is the preferred agent in this setting. While there is no evidence that ivermectin would benefit COVID-19 infection itself, it is a preferred treatment for chronic strongyloidiasis and prevention of chronic disease accelerating to disseminated disease. Case reports have appeared describing disseminated strongyloidiasis during the treatment of COVID-19.

While patients certainly may have coinfection with influenza A and COVID-19, negative polymerase chain reaction testing from upper and lower airway specimens is felt to be of sufficient negative predictive power to preclude treatment for influenza in patients with confirmed COVID-19.

Randomized controlled trials evaluating the role of pooled convalescent serum for COVID-19 infection provide little support for a benefit.12345

A 38-year-old man is admitted to the ICU for respiratory failure secondary to COVID-19 infection. He is not vaccinated for COVID-19 or influenza. Four months ago, he traveled to a remote region of Cambodia as a volunteer to a missionary team building a church. He lived in a tent and did not have access to indoor plumbing facilities. He used an outdoor shower and pit latrine. For the last month, when he was in Southeast Asia, he had an “upset stomach” with occasional vomiting and almost daily nonbloody diarrhea. No evaluation or treatment occurred.

One day after flying home, he noted a sore throat and fever. At this time, the health care facilities in his hometown were encountering a growing number of influenza A cases. Within 2 days, he noted cough and progressive shortness of breath, and he presented to the ED in extreme respiratory distress, with a nasal swab positive for COVID-19 and a polymerase chain reaction test negative for influenza. His chest radiograph revealed diffuse airspace filling consistent with COVID-19 pneumonitis. He was placed on high-flow nasal cannula, but in less than 3 h, he deteriorated and required intubation. After intubation and sedation, he appears synchronous with the ventilator set in the assist-control mode, with a tidal volume of 6 mL/kg predicted body weight and respiratory rate of 26/min. With an FIO2 of 0.6 and PEEP of 14 cm H2O, an arterial blood gas yields a pH of 7.34, PCO2 of 37, and PO2 of 93. The peak airway pressure is 29 cm H2O, and the plateau airway pressure is 23 cm H2O. The initial laboratory data are notable for a normal WBC count with 31% eosinophils on the differential count. After intubation, a specimen collected by deep suctioning is sent for repeat testing for viral pathogens and is again positive for COVID-19 and negative for influenza.

Footnotes

  1. SEEK Questionnaires ↩

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  3. La Hoz RM, Morris MI; AST Infectious Diseases Community of Practice. Intestinal parasites including Cryptosporidium, Cyclospora, Giardia, and Microsporidia, Entamoeba histolytica, Strongyloides, Schistosomiasis, and Echinococcus: guidelines from the American Society of Transplantation Infectious Diseases Community of Practice. Clin Transplant. 2019;33(9):e13618. PubMed ↩

  4. Marchese V, Crosato V, Gulletta M, et al. Strongyloides infection manifested during immunosuppressive therapy for SARS-CoV-2 pneumonia. Infection. 2021;49(3):539-542. PubMed ↩

  5. Requena-Méndez A, Buonfrate D, Gomez-Junyent J, Zammarchi L, Bisoffi Z, Muñoz J. Evidence-based guidelines for screening and management of strongyloidiasis in non-endemic countries. Am J Trop Med Hyg. 2017;97(3):645-652. PubMed ↩