Strongyloidiasis histologically mimicking eosinophilic folliculitis

ARTICLE

Auteur(s) : Serafinella P. CANNAVÒ, Fabrizio GUARNERI, Claudio GUARNERI

Department of Territorial Social Medicine, Clinica Dermatologica Policlinico Universitario, Via C. Valeria, Gazzi, 98125 Messina, (Italy)

Article accepted on 26/01/2004

Sometimes dermatological symptoms, such as rash, urticaria and pruritus, can disclose an intestinal parasitic disease.
Strongyloidiasis is an intestinal parasitosis caused by Strongyloides stercoralis, a small nematode endemic in Africa, South and Central America and Southeastern USA. Furthermore, immigrants in industrialised countries and travellers can run the risk of contracting this infection [1]. After its cutaneous penetration and migration to the lung, Strongyloides takes up residence in the upper intestine. The first skin penetration is often symptomless, but the diffusion of the larvae brings on systemic symptoms, such as bronchitis or pneumonitis, abdominal pain, diarrhea, nausea and vomiting, weight loss. These symptoms can be present above all in patients with immune deficiency or malnourition.
Peripheral blood eosinophilia is always present.
The skin manifestations usually include urticaria and pruritus, a serpiginous creeping eruption caused by the intradermal migration of the larvae, widespread petechiae, purpura and maculo-papular exanthema [2].

Case report

A 72-year-old Italian caucasian man, farmer, was referred to our Institute for a pruriginous erythematous-papular eruption, localized on his trunk, glutei and upper arms, of 4 years duration. The symptoms persisted although repeated topical and oral steroid therapy was carried out for a few days during the course of the disease. The cutaneous features were accompanied by generalized asthenia, and alternating diarrhoea and constipation. Furthermore a 7-kg weight loss was present in the 3 months preceding our observation. He denied any previous history of skin disease and his past medical history was unremarkable.
Examination revealed multiple reddish, pea-sized, round, slightly elevated papules on the chest, back, proximal thighs and upper arms (Fig. 1).
Laboratory tests disclosed a white cell count of 13,430 cells/mm³ with 8% eosinophils, erythrocyte sedimentation rate 22 mm in the first hour, hypergammaglobulinemia, elevated levels of IgG (1910 mg/dL) and of IgE (1000 mg/dL).
Skin biopsy specimens from a maculo-papular lesion showed extensive involvement of hair follicles with inflammatory cell infiltrate of eosinophil and neutrophil cells (Fig. 2); sebaceous lysis was absent.
On the basis of the marked eosinophilia and the clinical picture (alvus disorders, loss of weight, maculo-papular eruption, itching), a faecal examination for parasites was performed and, according to the Baermann method, larvae of Strongyloides stercoralis were found.
The patient was treated with albendazol (400 mg twice daily for three days), with healing of clinical symptoms and eosinophilia. On re-examination of the faeces no larvae were found.
After a follow-up of 24 months, the patient is still healthy.

Discussion

The present case shows a peculiar presentation of strongyloidiasis in an immunocompetent patient, who never moved from his country, so that he could not be considered a subject at risk for this kind of disease. Furthermore, the skin biopsy showed a particular histological pattern showing a perifollicular inflammatory cell infiltration composed predominantly of eosinophils and neutrophils. These histological changes, resembling eosinophilic folliculitis, could be interpreted as a hypersensitivity, folliculocentric, eosinophilic-mediated reaction [3], in analogy to what was shown in patients affected by other diseases, such as tinea infection [4]. Moreover, Czarnetzki and Springorum [5] described an analogous histological pattern in a patient affected by parasitic infestation, with typical larva migrans lesions associated with an itching papular folliculitis.
In the case here presented, the demonstration of Strongyloides stercoralis, by means of the sensitive Baermann technique [6] for parasitologic examination of faeces, was needed to achieve the diagnosis.
On the basis of this diagnosis albendazol therapy was performed, which is the treatment of choice together with ivermectin, to achieve the clinical resolution of the disease. n

References

1. Van der Klooster JM, Schelfhout LJ, Boldewijn JK. Recurrent, itching and creeping skin lesions in (former) travellers to the tropics: strongyloidiasis. Ned Tijdschr Geneeskd 2002; 146 (10): 477-81.

2. Gordon SM, Gal AA, Solomon AR, Bryan JA. Disseminated strongyloidiasis with cutaneous manifestations in an immunocompromised host. J Am Acad Dermatol 1994; 31 (2 Pt1): 255-9.

3. McCalmont TH, Altemus D, Maurer T, Berger TG. Eosinophilic folliculitis. The histologic spectrum. Am J Dermatopathol 1995; 17 (5): 439-46.

4. Kuo TT, Chen SY, Chan HL. Tinea infection histologically simulating eosinophilic pustular follicolitis. J Cutan Pathol 1986; 13: 118-22.

5. Czarnetzki BM, Springorum M. Larva migrans with eosinophilic papular folliculitis. Dermatologica 1982; 164 (1): 36-40.

6. Van der Feltz M, Slee PHThJ, van Hees PAM, Tersmette M. Strongyloides stercoralis infection:how to diagnose best? Neth J Med 1999; 55: 128-31.