"Turkey ear" as a cutaneous maniestation of tuberculosis

Cutaneous tuberculosis of the pinna

BACKGROUND

Cutaneous tuberculosis (CTB) rarely involves the ear as the primary site, but while diagnosing and treating ear infections, it should be considered a differential diagnosis in a tropical country such as India. The present study reports the incidence and clinical presentation of auricular tuberculosis (TB) in a tertiary care hospital in New Delhi.

METHODS

A retrospective, observational study was conducted from 2005 to 2019 whereby all cases of CTB confirmed by biopsy were retrieved from the database. The demographic details, clinical details, Mantoux results, and photographs were extracted and studied. The data were entered into MS Excel and analyzed.

RESULTS

In a retrospective analysis of 886 cases of CTB over a period of 15 years, we found 20 cases (2.26%) of ear involvement (1 case with bilateral involvement). The median age of the patients with ear involvement was 29 years with 42.11% men and 57.89% women. Morphological variants seen over pinna were predominantly classic plaque type (31.58%) and nodular (31.58%), with few ulcerative (21.05%) and tumoral forms (15.79%). CTB of the pinna showed predominant involvement of either helix or ear lobule (7 cases each). All cases were strongly positive to tuberculin and showed response to the empirical antitubercular treatment.

CONCLUSION

CTB can exclusively affect the pinna in varied presentations. The ear lobules and the helix are the usual sites of affection. It is rare for both ears to be affected with CTB, unlike bacilliferous leprosy. Regression following institution of antitubercular treatment is a reasonable way to confirm CTB.

Unusual presentations of cutaneous tuberculosis

Cutaneous tuberculosis occurs in 1-2% of world cases of tuberculosis and more common in tropical countries. It presents with different clinical forms. Unusual clinical presentations are not uncommon and awareness of these will help in suspecting and managing these patients successfully. Lupus pernio like lupus vulgaris, tuberculosis of glans penis and lichen scrofulosorum on the distal parts of limbs are presented here because of their unusual clinical presentation.

Cutaneous Tuberculosis

Cutaneous tuberculosis (TB) may present in various clinical manifestations. Skin involvement may occur as a result of exogenous inoculation, contiguous spread from a nearby focus of infection, or by hematogenous spread from a distant focus. Because the clinical presentation of cutaneous TB can vary widely, it is important to have a high index of suspicion in appropriate clinical settings. In this chapter, the various clinical manifestations of clinical TB are classified by source of infection (exogenous, endogenous, and hematogenous spread). These are linked to the clinical appearance and histology of the skin lesions. Hopefully, this will resolve the confusion created by the myriad of terms previously used in the medical literature. Once a diagnosis of cutaneous TB is entertained, a biopsy for both culture and histopathology should be submitted. In some cases histopathology may show nonspecific inflammation without classic granuloma formation. In these cases, monoclonal antibodies and polymerase chain reaction (PCR) testing may be useful. In fact, in recent years, PCR amplification has proven to be invaluable in assisting identification of M. tuberculosis from skin biopsies in patients with negative TB cultures. In most instances, treatment of cutaneous TB requires combination chemotherapy. This is especially important in patients with extra cutaneous disease, multiple skin lesions, and those with profound immunosuppression. Surgery also may play both a diagnostic and therapeutic role.