Cough syncope and multiple pulmonary nodules

Abstract

A 71-year-old farmer was admitted to the Intensive Care Unit because of acute respiratory failure following a 5-month history of chronic cough. His medical history included a tobacco smoking habit, and severe bilateral carotid stenosis. He had been suffering from exertional dyspnea for many years, but had never sought medical care. He had never travelled abroad, and was taking no medication. The vital signs were; blood pressure 135/85 mm/Hg, pulse 95 beats/min, respiratory rate 24 breaths/min, body temperature 37.3 C. The physical examination was unremarkable except for bilateral wheezing on lung auscultation. Arterial blood gas analysis on breathing room air showed pH 7.34, PCO2 48 mmHg, PO2 56 mmHg. Laboratory tests included a slightly elevated C-reactive protein level 46 mg/L, procalcitonin lower than normal 0.05 ng/ mL. The blood white-cell count was 10.6 cells/mm with marked hypereosinophilia (2040 cells/mm). The chest X-ray study showed no significant abnormality. A thoracic contrast computed tomography (CT scan) ruled out a pulmonary embolism, but showed bilateral nodules and patchy infiltrates, disseminated asymmetrically throughout lung parenchyma (Figs. 1, 2). The patient was initially treated with oxygen supplementation, antibiotics (amoxicilline clavulanate 1 g tid) and steroids (prednisone 40 mg/day), resulting in moderate improvement. Eosinophilia suggested multiple parasitological examinations of the feces; they were all negative. Nevertheless, 6 days after admission, immuno-enzymatic assay (ELISA) for Toxocara Canis appeared strongly positive. It was later confirmed by a western blot analysis. Closer questioning of the patient revealed that he was living alone with his dog after his wife had died 6 months prior. He had given up his daily work on the farm, and progressively had ceased cleaning up the dog’s feces. Intermittent dry coughing fits had then appeared, becoming increasingly frequent. Coughing had soon become permanent and disabling with several episodes of cough syncope that had led him to consult his general practitioner. Diagnosis Visceral larva migrans with pulmonary involvement caused by Toxocara Canis infection. Visceral larva migrans is a ubiquitous zoonosis resulting from infestation by the common roundworms of dogs and cats, Toxocara Canis and Cati, respectively [1]. The parasite undergoes a complete cycle in young dogs, which leads to the excretion of embryonated eggs in the environment. Human beings are infected after ingestion of the eggs, either via contaminated food, or (more commonly) via unwashed hands. The larvae that hatch from the eggs then invade the intestinal mucosa and disseminate to several organs, including the liver, the central nervous system and the lungs [1, 3]. In immunocompetent adult hosts, toxocarosis is most often asymptomatic, but can exhibit a wide variety of clinical features reflecting visceral spread of the larvae [1]. Mild, chronic infections usually presents with the clinical pictures of ‘‘covert’’ or ‘‘common’’ toxocariosis, while the term ‘‘visceral larva migrans’’ reflects more acute multiorgan presentations. Pulmonary involvement is reported in L. Kreitmann M. Lemyze Department of Respiratory and Critical Care Medicine, Schaffner Hospital, Lens, France