Senior Resident in Advanced Internal Medicine at Tan Tock Seng Hospital, Singapore
An Unusual Case Of Fever And Weight Loss
Introduction: Trichuris Trichuria (whipworm) infection is commonly asymptomatic, usual symptoms include asthenia, abdominal pain and diarrhea1. We present a case of pyrexia of unknown origin that was found to be due to an underlying whipworm infection.
Case description: A 61 year old healthy Chinese gentleman was referred from the Emergency Department to General Medicine Clinic for a 3-week history of intermittent fever, weight loss of 15 kg over 9 months, and constipation for 2 weeks . He was subsequently admitted for evaluation for pyrexia of unknown origin.
Preliminary investigations reviewed that he has a normochromic normocytic anaemia (Haemoglobin 10.9), with eosinophilia 1.2 x 10^9 (range 0.0-0.7), raised C-reactive protein 144.7 (range 0.0-0.50). Ferritin levels were also elevated at 503 (24-336).
During the admission, extensive investigations to look for infectious, autoimmune and malignancy causes were carried out.
All investigations were negative except for a third set of stool specimen of which Trichuris Trichuria ova was seen. He was treated with 3 days of albendazole and planned for outpatient endoscopic evaluation.
Upon review in outpatient clinic, he had gained weight, his anaemia and eosinophilia had completely resolved.
Discussion: Helminthic infections are known to downregulate the host’s immune system3. However, in this patient, there appears to be a marked immune response with fever, significant weight loss, and raised inflammatory markers. Helminth-induced eosinophilia is known to augment the production of cytokines and chemokine4, which might have been the case for this patient.
In developed countries, helminthic infections are often an almost forgotten cause of pyrexia. The possibility of parasitic infection should always be considered in the presence of eosinophilia.
1. Soil-transmitted helminth infections. Jourdan PM, Lamberton PHL, Fenwick A, Addiss DG. Lancet. 2017 Sep 4. pii: S0140-6736(17)31930-X.
2. Helminth infections and host immune regulation. McSorley HJ, Maizels RM. Clin Microbiol Rev. 2012 Oct;25(4):585-608.
3. Eosinophil-Mediated Tissue Inflammatory Responses in Helminth Infection. Shin MH, Lee YA, Min DY. Korean J Parasitol. 2009 Oct;47 Suppl:S125-31.