Recent advances in molluscum contagiosum virus research

Cytological diagnosis of molluscum contagiosum with an unusual clinical presentation at an unusual site

BACKGROUND

Molluscum contagiosum, is a common skin infection caused by a pox virus usually present as raised nodule with umbilicated centre. Cytologic diagnosis has been documented in very few case reports as the lesion is subjected to fine needle aspiration rarely and awareness of the cytological features of Molluscum contagiosum is limited. The cytological diagnosis is further challenging in clinically unsuspected lesions.

MAIN OBSERVATIONS

A 45-year-old female patient presented with 10 months history of a nodular nipple lesion which ulcerated after local application of caustic pencil. There was no associated breast lump. Cheesy material was expressed from the ulcer on the nipple and crush smeared on slides for cytological evaluation. Cytology smears revealed nucleate and anucleate squames in an inflammatory background. Characteristic intracytopalsmic and extracytopalsmic molluscum bodies were seen.

CONCLUSION

The nipple is an unusual site of presentation for Molluscum contagiosum. Ulcerated lesions are rarer. In the present case, the cytological examination facilitated the diagnosis in a clinically unsuspected case. Cytology can be a useful rapid diagnostic aid in planning the management of these patients and help in avoiding unnecessary biopsies.

Specimens from a vesicular lesion caused by molluscum contagiosum virus produced a cytopathic effect in cell culture that mimicked that produced by herpes simplex virus

Infection with molluscum contagiosum virus, a poxvirus, normally has a typical clinical presentation; therefore, laboratory confirmation is infrequently sought and the virus is rarely isolated in culture. As reported herein, viral culture of specimens from atypical lesions may produce an abortive infection in limited cell lines and a cytopathic effect suggestive of herpes simplex virus.

Replication of varicella-zoster virus in human skin organ culture

Varicella-zoster virus (VZV) infection is restricted to humans, which hinders studies of its pathogenesis in rodent models of disease. To facilitate the study of VZV skin tropism, we developed an ex vivo system using human fetal skin organ culture (SOC). VZV replication was analyzed by plaque assay, transmission electron microscopy, and histology. The yield of infectious VZV from SOC increased approximately 100-fold over 6 days, virions were abundant, and lesions developed that contained VZV antigens and resembled varicella and zoster lesions. The SOC system for VZV replication has applications for testing virus mutants and antiviral drugs.