MOLLUSCUM CONTAGIOSUM
Lidya Imelda Laksmi
CONTENTS
I. INTRODUCTION ……….. 1
II. POXVIRUS INFECTIONS ………... 2
III. INCIDENCE ………... 2
IV. PATHOGENESIS ………. 3
V. CLINICAL MANIFESTATIONS ……….. 3
VI. PATHOLOGY ………... 4
Microscopic ………. 4
VII. DIFFERENTIAL DIAGNOSE ……….. 5
MOLLUSCUM CONTAGIOSUM
Lidya Imelda Laksmi
Department Anatomic Pathology Medical Faculty Universitas Sumatera Utara
Introduction
Molluscum contagiosum is a common non-cancerous skin growth caused by a viral infection in the top layers of the skin. They are similar to warts but are caused by a different virus 1. Molluscum contagiosum, a cutaneous and mucosal eruption caused by a Molluscipox virus 2 (poxvirus 1,3,4), was first described and later assigned its name by Bateman in the beginning of the nineteenth century. In 1841 Henderson and Paterson described the intracytoplasmic inclusion bodies now known as molluscum or Henderson-Paterson bodies. In the early twentieth century, Juliusberg, Wile, and Kingery were able to extract filterable virus from lesions and show transmissibility. Goodpasture later described the similarities of molluscum and vaccinia. Though generally thought to infect only humans, but there are a few isolated reports of Molluscum contagiosum occuring in chickens, sparrows, pigeons, chimpanzees, kangaroos, a dog, and a horse. The infection is found worldwide and has higher incidence in children, sexually active adults, and those who are immunodeficient 1,2,5.
POXVIRUS INFECTIONS
Pathogenesis
This disease is transmitted primarily through direct skin contact with an infected individual. Fomites have been suggested as another source of infection, with molluscum contagiosum reportedly acquired from bath towels, tattoo instruments, and in beauty parlors and Turkish baths. The average incubation time is between 2 and 7 weeks with a range extending out to 6 months. Infection with the virus causes hyperplasia and hypertrophy of the epidermis. Free virus cores have been found in all layers of the epidermis. So-called viral factories are located in the malpighian and granular cell layers. The molluscum bodies contain large numbers of maturing virions. These are contained intracellularly in a collagen-lipid-rich saclike structure that is thought to deter immunological recognition by the host. Rupture and discharge of the infectious virus-packed cells occur in the center of the lesion. MCV induces a benign tumor instead of the usual necrotic pox lesion associated with other poxviruses 2.
Reed and Parkinson studied the histogenesis of molluscum contagiosum and concluded that the lesion arises on the basis of follicular neogenesis. They found areas of hair bulb differentiation at the periphery, occasionally associated with areas of sebaceous gland differentiation. However, the disease can also appear in places where there are no hair follicles, such as the palms, indicating that the epidermis itself may be affected 7,8.
Clinical manifestations
both genital and nongenital areas. MCV in adults affects the groin, genital area, thighs, and lower abdomen and is often acquired sexually. Around 10% of cases develop an eczematous dermatitis around the lesions, but this disappears as the infection resolves. Patients with atopic dermatitis can have a disseminated eruption. Eruption in immunocompromised individuals are very resistant to treatment 2,3.
A B
A. The typical molluscum contagiosum lesion is a small firm umbilicated papule with a smooth, waxy, or pearly surface. B. Molluscum Contagiosum in a patient with the acquired immunodeficiency syndrome
PATHOLOGY
Microscopic
Smears of these lesions are easily obtained by squeezing the lesion and expelling its core on a slide that may be immediately examined after methylene blue staining 9, Giemsa 2,3, Gram, Wright, Papanicolaou 2. The smears show a large number of “molluscum bodies”, which are squamous cells filled with masses of viral particles, displacing the nucleus to the periphery 9,10.
discharge their contents. 3,4,5,6,7.
Hematoxylin and Eosin. A biopsy revealed lobules of keratinocytes containing large eosinophilic intracytoplasmic inclusion bodies (Henderson-Patterson, or molluscum bodies).
Differential Diagnose
proliferation of endothelial cells. Ultrastructural studies show viral particles within the cytoplasm of degenerating epidermal cells 4.
REFERENCES
1. Molluscum contagiosum, available at:
www.djo.harvard.edu/site.php?url=/physicians/oa/674
2. Molluscum contagiosum, available at:
sexualhealthcare.net/sexually-transmitteddiseases-molluscumcontagiosum
3. Murphy GF, Sellheyer Klaus, Mihm MC. The Skin. In: Robbins and Cotran Pathologic Basis of Disease. 7th edition. Philadelphia: Elsevier Saunders. 2005; 1266-7.
4. Wetherington RW, Khan ZM, Cockerell CJ. Viral Infections. Barnhill RL, editor. In: Textbook of Dermatopathology. Second edition. McGraw-Hill. 2004; 531-3
5. Andrews GC. Some Virus and Rickettsial Diseases. In: Diseases of the Skin For Practitioners and Students. Fourth edition. Philadelphia and London: W.B.Saunders Company. 1961; 482-5
6. Robboy SJ, Duggan MA, Kurman RJ. The Female Reproductive System. In: Rubin E, Farber JL, editors. Pathology. 3rd edition. Philadelphia: Lippincott Williams & Wilkins. 968. 7. Rosai Juan. Skin. In: Ackerman’s Surgical Pathology. Volume 1. 8th edition. Mosby. 1989;
67.
8. Molluscum contagiosum, available at: www.forces-of-nature.net/sitemap.php?cid=5
9. Koss LG, Melamed MR. The Skin. In: Koss’ Diagnostic Cytologic and Its Histopathologic Bases. Volume II. 5th Edition. Philadelphia: Lippincott Williams & Wilkins. 2006; 1288. 10. Koss LG, Melamed MR. Diseases of the Vagina, Vulva, Perineum, and anus. In: Koss’
