Immunohistochemistry as test of cure in an immunodeficient patient with recurrent urogenital ulcers caused by an infection with Aciclovir-resistant herpes simplex virus-2

Background:

The psychological and somatic strain in patients with chronic, recurrent herpes simplex virus- (HSV) infections is high. Standard diagnostics involve the evaluation of characteristic clinical symptoms, serologic testing and the direct detection of HSV in body fluids and tissues. Aciclovir is commonly used in the prevention and treatment of HSV-infections. Immunodeficient patients are more likely to get infected by HSV.

Case report:

A 54-year old woman receiving chemotherapy for acute myeloid leukemia (AML) presented in our hospital with severe genital itching and burning. The patient had a history of recurrent genital herpes and received oral Valaciclovir for Epstein Barr Virus-prophylaxis. Sporadic treatments with oral and topical Aciclovir achieved only short-term relief. The clinical examination showed ulcerous and purulent lesions in the urogenital area.

A smear (HSV-2 positive) and a punch biopsy (immunohistochemically HSV-1/-2 positive) were taken. Resistance testing revealed Foscarnet sensitivity and Aciclovir resistance.

After receiving intravenous Foscarnet for ten days, the patient reported no symptoms anymore and the pre-discharge gynecological examination found no residual disease. The test-of-cure biopsy was negative for HSV-1 and HSV-2. The patient was discharged in well-being and reported no recurrence in a long-term checkup conducted six months later.

Discussion:

Histological-based resistance testing and consequent targeted therapy has led to a treatment change and to a quick and long-term clinical remission in this patient. These aspects are important especially in immunodeficient patients, who suffer in about 7% of multiresistant genital HSV infections.