Generalized eruptive keratoacanthoma

Generalized eruptive keratoacanthoma: proposed diagnostic criteria and therapeutic evaluation

Generalized eruptive keratoacanthoma (GEKA) of Grzybowski is a sporadically occurring, extremely rare variant of keratoacanthoma characterized clinically by severely pruritic, generalized eruption of numerous small follicular papules, often with a central keratotic plug, and histologically by typical features of solitary keratoacanthoma. Despite the continuous addition of new case reports, no definite diagnostic criteria have been established, and an optimum treatment is not yet determined. Herein, we review the different aspects of this rare entity, including pathogenesis, clinical and histopathological features, differential diagnosis, course and prognosis. Different therapeutic approaches and their impact on the course and prognosis of the disease are also evaluated and presented. We propose two sets of diagnostic criteria to define the disease more precisely and to avoid overlapping and confusion with other types of multiple keratoacanthoma. The first set comprises constant clinical and histopathological features that almost always present in every case and the second set includes variable features that were reported in some patients, and to which any emerging finding could be added to avoid missing cases. Although different therapeutic options have been used, either as single agents or in combinations, there is no standard therapy for GEKA and the disease still represents a therapeutic challenge.

Grzybowski's generalized eruptive keratoacanthoma: Remission with cyclophosphamide

A 57-year-old woman presented with intensely pruritic generalized eruptive keratoacanthomas affecting cutaneous and mucosal surfaces (Grzybowski syndrome). She derived marginal benefit from anti-pruritic agents, acitretin and methotrexate. However, cyclophosphamide 100 mg daily for 1 month followed by 3 months at 200 mg daily resulted in remarkable improvement and eventual remission without further treatment. The disease resulted in severe ectropion of upper and lower eyelids bilaterally. Two years after the onset of her disease, the lower lid ectropions were repaired using skin grafting. There was no evidence for papillomavirus infection.

Generalized eruptive keratoacanthoma of Grzybowski

A patient with generalized eruptive keratoacanthoma of Grzybowski is described. Our findings, along with those of the 21 reported cases from the world literature, are summarized. This rare variant of keratoacanthoma most commonly affects patients in the fifth to seventh decades of life and appears as a generalized eruption of hundreds to thousands of follicular papules. These small papules often have a keratotic center and demonstrate the microscopic features of keratoacanthoma. Marked facial involvement is characteristic and can lead to masked facies with ectropion. Severe pruritus, mucosal lesions, and koebnerization are features of the disease. The course is chronic and the response to therapy is poor, although a few patients have improved with the use of systemic retinoids.