Human T cell lymphotropic virus 1 associated infective dermatitis in KwaZulu-Natal, South Africa.

Abstract

Background

Human T cell Lymphotropic Virus Type I (HTLV-I) associated infective dermatitis, first

described by Sweet in Jamaican children, is a pattern of eczema characterized by

exudation, crusting around the nostrils, ears and scalp with eventual appearance of a

generalized fine papular rash. More recently LeGranade and co-workers have proposed major and minor criteria in establishing the diagnosis of HTLV-I associated infective

dermatitis (HAID).

HTLV-I has been aetiologically linked to Adult T cell leukaemia/lymphoma (ATLL) and tropical spastic paraparesis (TSP). HAID is not only a marker of childhood infection with HTLV-I but may be a harbinger of more serious HTLV-I associated diseases later on in life such as ATLL or TSP. The pathogenesis of HAID is poorly understood so are the histopathological features of this entity. The effects of co-infection with human

immunodeficiency virus- 1 (HIV-1) are inconclusive.

HAID is described in Sub Saharan Africa, Senegal but no data is published on this entity in Southern Africa, characterizing the clinical, laboratory features and the histopathology

of this entity.

Aims and Objectives

1) To describe the clinical and histological features of HTLV-I associated infective

dermatitis in KZN, South Africa

2) To determine the virological characteristics of HTLV-I in KZN, South Africa

3) To assess for HTLV-I / HIV co-infection

Methods

This was a prospective study of all patients with HAID who presented to King Edward VIII hospital (KEH), outpatient department over a period of 42 months. These were

patients who fulfilled the clinical criteria of HAID. Enrolled patients were subjected to a

confirmatory HTLV-I serology testing. Demographic data was obtained from all HTLV-I

seropositive patients. Their clinical examination included dermatological, neurological

and pathological examination. A blood count, immunoglobulin levels, serum protein

electrophoresis measuring albumin levels and globulin fractions were measured. For

bacteriological assessment skin swabs were taken from the affected sites with stool

samples examined for parasites, ova and cysts.

The HIV-1 status together with HIV-1 viral load were determined on those enrolled. The

CD4 count, CD8 counts and CD4/CD8 ratio were also calculated. Skin biopsies were

taken for histological examination. PCR for HTLV subtyping was performed on a subset of the cohort.

Results

Demography

Of the 60 patients recruited, 33 fulfilled criteria for HAID. The majority of patients fell

between age categories of 6 to lOyears. The male to female ratio was 1:1. There were

more females in the adult group than there were within the childhood group. All of the

patients in our cohort were African.

Clinical features

The lesions were erythematous, scaly, exudative, and crusted in all cases. The distribution

of lesions was as follows: scalp (77.4%), retroauricular areas (71%), the axilla (65%) and

paranasal areas (58%) were the sites more commonly affected. Nasal crusting was not a

significant feature in this series.

Bacteriology

Culture was positive for Staphylococcus aureus (S. aureus) in 90%, with streptococcal

group of organisms found in 68% of the skin swabs taken from the lesional skin.

Haematological

Our patients were mildly anaemic as has been shown in previous studies. They had a mean Hb of 11.5g/dl. In 12 of the 14 patients tested, the erythrocyte sedimentation rate

(ESR) was elevated. Serum protein electrophoresis and levels of Immunoglobulin A, G

and M were raised. The mean CD4 count in the entire group was elevated at 1730

cells/fil, CD8 was 1299 cells/ul

Histopathology

The major histological findings were as follows: 38% demonstrated a superficial and

deep perivascular inflammatory infiltrate, 28% had a superficial and deep perivascular

inflammatory infiltrate together with a lichenoid dermatitis, 12.9% had features of

superficial and deep inflammatory infiltrate with an interface dermatitis, 6.4% revealed features of seborrhoeic dermatitis.

Genotyping

Our patients were infected with the strains belonging to the Cosmopolitan, A Subtype (HTLV-Ia).

Complications

Complications were low in this series with the commonest being scabies in 6(18.1%), corneal opacities in 3(8.6%), 2(6 %) with HAM/TSP. No parasitic worm infestations

were isolated.

HIV/HTLV-I co-infection

Of the 33 patients, 9 (30 %) were co-infected with HIV. The mean viral load in this group was 52 000 copies/ml. Their mean CD4 count was also elevated at 1505cells/^il with a

CD8 of 1704 cells/Mi and a CD4/CD8 ratio of 1.15.

Discussion

Thirty three of the 60 patients enrolled met the diagnosis for HAID according to the

established criteria. The mean age in this series was 17 years (range: 8 months-46 years)however; almost a third (30.3%) were children under 12 years, reinforcing the entity as a

childhood infective condition.

There was an equal male female distribution in the childhood group and a female

predominance in the adult group.

Clinically patients presented with infected erythematous, scaly lesions mainly on the scalp, neck and post- auricular area. The clinical features were in keeping with other

series worldwide. The complication rate was low in our cohort.

S. aureus was the predominant organism in both anterior nares and lesional skin. The

most common histological pattern was superficial and deep perivascular inflammatory

infiltrate. The subtype in our series was the Cosmopolitan Subtype A (HTLV-Ia) as opposed to subtype B in Japan. We share with Brazil a common subtype.

A subset of our patients (30%) was co-infected with HIV. The CD4 cell count in this

subgroup was lower than the entire group but this was not statistically significant. The

histological patterns found in this subgroup infected with HIV were similar to the rest of the group except for a more intense eosinophilic infiltrate in these skin biopsy specimens.

Conclusion

HTLV-I associated infective dermatitis is distinct entity which affects the African population of KwaZulu Natal, South Africa. It is predominantly a disease of childhood

with an equal female to male ratio in children. The clinical features are an exudative,

erythematous scaly rash most commonly found involving the scalp, axillae, paranasal and

retroauricular areas. HTLV-I positivity is essential for the diagnosis; the Cosmopolitan

Subtype A is commonest in South Africa. The commonest histological pattern is a

superficial and deep perivascular infiltrate in 38%. A subset, 30%, was co-infected with

HIV.