2001 Case #10

Universidad Peruana Cayetano Heredia
(Links to Other 2001 Cases are at bottom of this page)
The following case was seen in the outpatient department of the Tropical Medicine Institute of Cayetano Heredia Hospital in Lima by the 2001 Gorgas Course participants.
Image for 03/26/01History: 53 yo female housewife with many years of non-specific skin symptoms. Over the previous 2 years this has progressed to a chronic dermatitis initially involving arms, shoulders, and axilla but spreading in recent months to involve buttocks and legs. Intensely pruritic, unable to sleep. No fever, no weight loss or systemic symptoms. No history of TB or exposure. Has had diagnoses of eczema, allergic dermatitis, and psoriasis, with intermittent treatment with antihistamines and local steroids.

Epidemiology: Lifelong resident of Lima except for 1 year in the jungle many years ago. Parents from Ayacucho and Abancay in the high Andes. No history of blood transfusions, IV or other illicit drugs; monogamous.

Physical Examination: Afebrile. Skin lesions identical to those in photograph diffusely on body.  No organomegaly or lymphadenopathy.

Labs/X-ray: Hct 36. WBC 7.6 with 68 segs, 1 bands, 28 lymph, 3 eos. Normal chest x-ray. HIV ELISA negative.


University of Alabama at Birmingham

2001 Case #10
Diagnosis and Discussion

Universidad Peruana Cayetano Heredia

Diagnosis: Norwegian (crusted) scabies secondary to HTLV-1 infection.
Discussion: Skin scrapings viewed by direct microscopy disclosed 2-3 Sarcoptes scabei per each high power field, a remarkable density. ELISA and Western blot for HTLV-1 were both positive in the patient as well as in both her parents who are in their 70s.

The crusted diffuse highly pruritic skin lesions in this patient are very characteristic for Norwegian scabies. This condition is well described in many immunocompromising conditions including HIV infection, malignancy, and immunosuppressive therapy. The skin is hyperinfested with thousands of mites, so it is easily diagnosable with simple scrapings. The lesions are highly infectious and present a serious nosocomial risk.

At the Tropical Medicine Institute in Lima approximately 70% of all cases of Norwegian scabies are associated with HTLV-1 infection and are, in the absence of any other factors, associated with immunosuppression. Other opportunists associated with HTLV-1 are strongyloides infection (negative Baermann stool concentration in our patient) and onychomycosis.

Other conditions associated with HTLV-1 infection are acute T-cell leukemia/lymphoma (normal blood film in this patient) and autoimmune disease including tropical spastic paraparesis, Sjogrens, and thyroiditis. Neither this patient nor her parents had any neurological findings.

The prevalence of HTLV-1 in South America is generally underappreciated, normally being associated with Japanese and Caribbean populations. In Peru, the disease is highly endemic (2-3% seropositivity) in Andean areas of the country, in Quechua populations who have had no contact with Japanese immigrants to the country. Other South American countries with significant rates of HTLV-1 include Brazil, Colombia, and Ecuador. Transmission appears to be mainly vertical with high associations with breastfeeding and duration of breastfeeding (probable route in our patient). Transfusion, sexual transmission, and IV drug abuse are much less important.

Norwegian scabies is not responsive to normal topical agents such as benzyl benzoate or permethrin. Our patient was treated with ivermectin 200 micrograms/kg bid for 2 days which was repeated 15 days later. The lesions responded dramatically to therapy.