Juvenile ecthyma gangrenosum caused by Pseudomonas aeruginosa revealing an underlying neutropenia: case report and review of the literature.

BACKGROUND

Ecthyma gangrenosum (EG) is characterized by the occurrence of erythematous, violaceous or haemorrhagic macules and/or vesicles, often evolving into necrotic ulcers, with a central grey-black eschar. It is a rare skin condition, usually occurring in immunocompromised patients suffering from bacterial sepsis caused by Pseudomonas aeruginosa. However, seemingly healthy children have been diagnosed with this skin disease as well.

OBJECTIVES

We report the workup of a case of vulvar EG caused by P. aeruginosa in a toddler, which led to a diagnosis of an underlying neutropenia. Moreover, we provide a brief literature review on those cases of EG where an underlying primary immunodeficiency, neutropenia in particular, was eventually diagnosed.

METHODS

A one-and-a-half-year-old girl presented with a history of recurrent (respiratory) infections and the sporadic occurrence of purpuric, vulvar ulcers. Workup consisted of microbiological and haematological investigations, including repeated blood analyses.

RESULTS

Bacterial swabs from the vulvar ulcers showed the growth of P. aeruginosa. No concomitant sepsis was present, but laboratory investigations pointed towards a cyclic neutropenia, coinciding with the occurrence of the EG lesions. Topical gentamicin ointment allowed the skin lesions to heal faster. Following the administration of granulocyte colony-stimulating factor (G-CSF), the girl experienced less infections in general and had no recurrence of EG lesions in particular. Treatment with G-CSF could eventually be stopped, and the neutropenia, ultimately transient in nature, completely resolved.

CONCLUSION

Children presenting with (anogenital) EG should always alert a physician to consider a potentially underlying immunodeficiency, neutropenia in particular.