D Sarma, S Panganiban, D Albertson
condyloma acuminatum, hpv, scabies
D Sarma, S Panganiban, D Albertson. Diagnostic Microscopic Images: Condyloma Acuminatum and Scabies. The Internet Journal of Dermatology. 2008 Volume 7 Number 1.
Diagnostic microscopic images of condyloma acuminatum and scabies are presented with a brief discussion of the diagnostic features.
Biopsy of a 5-mm raised skin lesion from the vulva of a 25-year-old woman.
Diagnosis: Condyloma acuminatum with positive low risk HPV.
Condyloma acuminatum (genital wart) is the most common viral sexually transmitted disease in the United States and is caused by human papilloma virus (HPV). Over seventy subtypes of HPV exist. Approximately half of these subtypes are specific for the anogenital epithelium and have varying potentials for malignant transformation. Low-risk subtypes, including HPV 6 and 11, do not integrate into the host genome and are most frequently associated with benign condylomas and low grade intraepithelial neoplasia [1,2,3,4].
Histologic examination of the skin (Figs. 1 and 2) lesion demonstrates papillomatosis accompanied by the characteristic features of acanthosis, parakeratosis, and hyperkeratosis. Koilocytosis of the keratinocytes suggests active viropathy. Such virus-infected keratinocytes show perinuclear clearing around large, centrally located nuclei with ground glass chromatin. Confirmation of low-risk HPV infection is achieved by FISH (Filter in situ hybridization), which demonstrates dark nuclear staining of the koilocytes (Figs.3 and 4).
Biopsy of an extremely pruritic rash on the right hand of a 20-year-old man with similar rash on the left foot. Previous biopsy was non-diagnostic.
Scabies results from infestation by the mite
Histologically, the lesion caused by the mite is the burrow that it creates within the stratum corneum. The burrow may go as far down as the stratum granulosum. The irritative effect of the mite's presence within the epidermis results in parakeratosis, spongiosis, vesiculation and eosinophilic infiltrates. Visualization of the mite, its egg(s) or feces is needed in order for definitive diagnosis. As depicted in Figure 5, the mite has a chitin exoskeleton with spines on its dorsal surface (A) that allow it to anchor itself within the epidermis. It also shows the internal organs (B) and two eggs (C).
Deba P Sarma, MD
Department of Pathology
Creighton University Medical Center
Omaha Nebraska USA 68131