History

Fact Explanation
Papules like " water blisters", occur in crops over 6-12 months this is a common skin infection of child hood (affect any age, but target group is children over one year [2]) Molluscum Contagiosum virus (MCV) is a double- stranded DNA virus in the family of poxviridae. These papules contain foci of epithelial hyperplasia, infected keratinocytes & are infiltrated with inflammatory cells. MCV has an ability to escape from local immune mechanisms. Genes in these pox viruses target the genes in main host immune mechanisms. ( MHC class 1, chemokines, IFNs, ILs). Once infected the immunogenicity of those host cells is reduced. [3]
Itching Seen in patients who are having atopy [1]
Excoriated lesions Secondary bacterial infections [1]
Eye lid lesions, itching, redden, tearing eyes These are seen in ocular molluscum contagiosum. Patients who have Acquired immune deficiency syndrome, atopic dermatitis, arthritis and patients on steroid treatment are more likely to get it. Eye lid lesion is the commonest finding. But conjunctivitis, keratoconjunctivitis are also seen which are thought to be caused by toxicity & hypersensitivity to the viral proteins released from the eyelid lesions. [4]
References
  1. BUXTON PAUL K. Viral infections. In:BUXTON PAUL K. ABC of dermatology. 4th ed. London: BMJ Books,2003,pp 93- 94
  2. SCHOFIELD O.M.V., REES J.L. Skin diseases. In:DAVIDSON STANLEY. ed. Nicki R. Colledge, ed. Brian R. Walker, ed. Stuart H. Ralston. Davidson's principles & practice of Medicine. 21st ed. London: Elsevier, 2010,pp 1273
  3. VERMI WILLIAM, FISOGNI SIMONA, SALOGNI LAURA, SCHäRER LEO, KUTZNER HEINZ, SOZZANI SILVANO, LONARDI SILVIA, ROSSINI CRISTINA, CALZAVARA-PINTON PIERGIACOMO, LEBOIT PHILIP E, FACCHETTI FABIO. Spontaneous Regression of Highly Immunogenic Molluscum contagiosum Virus (MCV)-Induced Skin Lesions Is Associated with Plasmacytoid Dendritic Cells and IFN-DC Infiltration. J Investig Dermatol [online] December, 131(2):426-434 [viewed 13 May 2014] Available from: doi:10.1038/jid.2010.256
  4. SCHORNACK MM, SIEMSEN DW, BRADLEY EA, SALOMAO DR, LEE HB. Ocular manifestations of molluscum contagiosum. Clin Exp Optom [online] 2006 Nov, 89(6):390-3 [viewed 14 May 2014] Available from: doi:10.1111/j.1444-0938.2006.00073.x

Examination

Fact Explanation
Single/Multiple, round, dome shaped, translucent papules (seems like fluid filled vesicles but in fact solid) these are pearly white/ skin colored. [2] These papules are circumscribed, raised lesions. [1] These papules contain foci of epithelial hyperplasia, infected keratinocytes & are infiltrated with inflammatory cells. [5]
1-3 mm in diameter has a central umbilication -punctum [2] Typical lesions are of 1-3 mm size. Early lesions are smaller than this. Atypical lesions are larger than this. > 15mm sometimes. [4] By squeezing the papule curd like white material can be expressed through umbilication.
Lesions found commonly in face,hands, lower abdomen & genitals. Lesions are more common in trunk, limb & face in the children. In the genitals, inner thighs and abdomen in adults [4] Lesions spread by autoinoculation. Close sexual contact also is a way of transmission. [4]
Kobner phenomenon is seen [2] ( i.e. new lesions occur at sites of skin trauma) [1]
Red eye, tearing, eye lid lesions These are manifestations of ocular molluscum contagiosum. Patients who have Acquired Immune Deficiency Syndrome (AIDS), atopic dermatitis, arthritis and patients on steroid treatment are more likely to contract this virus. They can also have findings compatible with above, e.g joint swelling & redness, cushingoid features etc. Conjunctivitis, keratoconjunctivitis thought to be caused by toxicity and hypersensitivity to the viral proteins released from the eyelid lesions. [3]
References
  1. BUXTON PAUL K.Viral infections. In:BUXTON PAUL K. ABC of dermatology. 4th ed. London: BMJ Books,2003,pp 93- 94
  2. PAIGE D.G. Skin diseases. In:KUMAR PRAVEEN, MICHAEL CLARK. Kumar & Clark's clinical medicine. 7th ed. London: Elsevier, 2009,pp 1232
  3. SCHORNACK MM, SIEMSEN DW, BRADLEY EA, SALOMAO DR, LEE HB. Ocular manifestations of molluscum contagiosum. Clin Exp Optom [online] 2006 Nov, 89(6):390-3 [viewed 14 May 2014] Available from: doi:10.1111/j.1444-0938.2006.00073.x
  4. HUGHES CHRISTINE M., DAMON INGER K., REYNOLDS MARY G., RAMSEY KYLE. Understanding U.S. Healthcare Providers’ Practices and Experiences with Molluscum Contagiosum. PLoS ONE [online] 2013 October [viewed 18 May 2014] Available from: doi:10.1371/journal.pone.0076948
  5. VERMI WILLIAM, FISOGNI SIMONA, SALOGNI LAURA, SCHäRER LEO, KUTZNER HEINZ, SOZZANI SILVANO, LONARDI SILVIA, ROSSINI CRISTINA, CALZAVARA-PINTON PIERGIACOMO, LEBOIT PHILIP E, FACCHETTI FABIO. Spontaneous Regression of Highly Immunogenic Molluscum contagiosum Virus (MCV)-Induced Skin Lesions Is Associated with Plasmacytoid Dendritic Cells and IFN-DC Infiltration. J Investig Dermatol [online] December, 131(2):426-434 [viewed 13 May 2014] Available from: doi:10.1038/jid.2010.256

Differential Diagnoses

Fact Explanation
Viral warts Sometimes the skin lesions of Molluscum Contagiosum are difficult to differentiate from viral warts [1]
Basal cell carcinoma In an immunocompromised patient ( i.e. HIV positive) molluscum contagiosum infection is hard to identify as lesions are atypical. [2]
Keratoacanthoma This also comes to a differential when found atypical lesions. Keratoacanthoma is a tumor grows rapidly & has histology resembling squamous cell carcinoma. [2] [3]
Cutaneous cryptoccosis Patients having atypical lesions give rise to the suspicion of this opportunistic infection. [2]
References
  1. BUXTON PAUL K. Viral infections. In:BUXTON PAUL K. ABC of dermatology. 4th ed. London: BMJ Books,2003,pp 93- 94
  2. FILO-ROGULSKA MARTA, PINDYCKA-PIASZCZYńSKA MALGORZATA, JANUSZEWSKI KRZYSZTOF, JARZąB JERZY. Disseminated atypical molluscum contagiosum as a presenting symptom of HIV infection. pdia [online] 2013 December, 1:56-58 [viewed 14 May 2014] Available from: doi:10.5114/pdia.2013.33380
  3. ESPINOZA W, PEREZ C, CUEVAS P. Keratoacanthoma BMJ Case Rep [online] :bcr09.2008.0995 [viewed 19 May 2014] Available from: doi:10.1136/bcr.09.2008.0995

Investigations - for Diagnosis

Fact Explanation
This is mainly a clinical diagnosis [2] Typical lesions are easy to identify by proper clinical examination. Single/Multiple, round, dome shaped, translucent papules (seems like fluid filled vesicles but in fact solid). Pearly white/ skin colored. 1-3 mm in diameter has a central umbilication -punctum [4]
Microscopy of the lesion Histopathological confirmation is considered in atypical lesions. This will show -cup like epidermal hyperplasia. Large inclusion bodies (molluscum bodies) in cells of stratum corneum and granulosum layers of skin (presence of molluscum bodies is diagnostic), numerous virions in the inclusion bodies (virus replicate inside the cellular cytoplasm causing the infected cell increasing in size, eventually this virions form inclusion bodies in size of 35 microns) [1] [3]
References
  1. BALIGA R.R. Molluscum Contagiosum. In:BALIGA R.R. 250 cases in clinlcle medicine. 3rd ed. London: W.B. Saunders, 2004,pp 494
  2. BUXTON PAUL K.Viral infections. In:BUXTON PAUL K. ABC of dermatology. 4th ed. London: BMJ Books,2003,pp 93- 94
  3. RAO KAVITA, PRIYA NS, UMADEVI HS, SMITHA T. Molluscum contagiosum. J Oral Maxillofac Pathol [online] 2013 December [viewed 13 May 2014] Available from: doi:10.4103/0973-029x.110726
  4. PAIGE D.G. Skin diseases. In:KUMAR PRAVEEN, MICHAEL CLARK. Kumar & Clark's clinical medicine. 7th ed. London: Elsevier, 2009,pp 1232

Investigations - Screening/Staging

Fact Explanation
HIV screening In an adult with extensive lesions, this gives rise to the suspicion of underlying immunosuppressed state. Atypical lesions commonly seen in immunocompromised patients. Atypical lesions are larger than the typical lesions (up to 15mm). There are a large number of lesions. These lesions coalesce together and form nodules. [1] [2]
References
  1. BALIGA R.R. Molluscum Contagiosum. In:BALIGA R.R. 250 cases in clinlcle medicine. 3rd ed. London: W.B. Saunders, 2004,pp 494
  2. FILO-ROGULSKA MARTA, PINDYCKA-PIASZCZYńSKA MALGORZATA, JANUSZEWSKI KRZYSZTOF, JARZąB JERZY. Disseminated atypical molluscum contagiosum as a presenting symptom of HIV infection. pdia [online] 2013 December, 1:56-58 [viewed 14 May 2014] Available from: doi:10.5114/pdia.2013.33380

Management - General Measures

Fact Explanation
Avoid direct contact by avoiding contact sports such as swimming is also advised. Avoid sharing fomites such as sharing towels, razors, clothes, make up etc and disinfect them after use. Avoid contact with the lesions, keep them covered by using cloths, bandages or any possible way. Maintain good hand hygiene This virus transmits via contact. So avoiding contact with the skin lesions and with the contaminated objects are ways of avoiding infection. Auto inoculation is also seen. This causes the virus to spread to other parts of the body. [1]
Safe sexual practices, maintain a monogamous sexual relationship with a known disease free person. This virus is known to transmit via sexual contact. [1]
In immunocompetent this resolve spontaneously This is a self- limiting skin infection. It takes 6- 12 months to achieve a spontaneous recovery.[1]
References
  1. Hughes CM, Damon IK, Reynolds MG. Understanding U.S. healthcare providers' practices and experiences with molluscum contagiosum. PLoS ONE. [online]2013;8(10):e76948.[viewed 18th May 2014] Available from: doi:10.1371/journal.pone.0076948

Management - Specific Treatments

Fact Explanation
Curettage - with or without light electrodissection. In this method the individual lesion is removed. As this is an invasive method anesthetic cream should be used prior to the curettage. Curettage provides reliable tissue samples for tissue diagnosis. [1]
Cantharidin- 0.9% sollution of collodion & acetone This is a blister inducing agent. Cantharidin is carefully applied to the dome of the lesion and after 4 hours it should be washed off. As this can cause severe blistering first test on few lesions. Don't use on facial lesions. treatment should be repeated weekly till patient is free of lesions. [1]
Cidofovir cream (3%) This is a nucleoside analog, has antiviral effects. This can be locally applied as a cream. [1]
5% imiquimod cream Exact mechanism of action of imiquimod is not known. This activates immune cells via Toll like receptor 7(TLR7) which is situated in cell surface & helps to recognize pathogens. Secretes cytokines from immune cells (IFN alpha, IL 6, TNF alpha). Activates Langerhan cells which in turns activates the adaptive immune system. Also activates Natural killer cells, Macrophages & B Lymphocytes. Local application of imiquimod stimulate innate immune system & cell mediated immunity. It has an antiviral and antitumour activity. [4]
Antibiotic- hydro cortisone ointment For secondarily infected excoriated lesions [2]
Local application of potassium hydroxide- 10%- 15% This is a safe, effective way of treating Molluscum Contagiosum. It has less side effects, easy to use & also it is proven to decrease the number of dermatology referrals. This is applied on all lesions twice daily using a cotton swab. If the patient gets a superficial ulcers or inflammatory response, stop the treatment. [5]
Pulsed dye laser This method of treatment is well tolerated, no residual scars or pigmentation is noted after the treatment. [1]
References
  1. CHAUDHARY M, KULKARNI M. Molluscum contagiosum in human immunodeficiency virus infected patients. Indian J Dent Res [online] 2008 Apr-Jun, 19(2):155-9 [viewed 14 May 2014] Available from: http://www.ncbi.nlm.nih.gov/pubmed/18445935
  2. BUXTON PAUL K. Viral infections. In:BUXTON PAUL K. ABC of dermatology. 4th ed. London: BMJ Books,2003,pp 93- 94
  3. BALIGA R.R. Molluscum Contagiosum. In:BALIGA R.R. 250 cases in clinlcle medicine. 3rd ed. London: W.B. Saunders, 2004,pp 494
  4. PURI NEERJA. A study on the use of imiquimod for the treatment of genital molluscum contagiosum and genital warts in female patients. Indian J Sex Transm Dis [online] 2009 December [viewed 13 May 2014] Available from: doi:10.4103/0253-7184.62763
  5. MARSAL JOSEP R, CRUZ INES, TEIXIDO CONCEPCIO, DIEZ OLGA, MARTINEZ MIREIA, GALINDO GISELA, REAL JORDI, SCHOENENBERGER JOAN A, PERA HELENA. Efficacy and tolerance of the topical application of potassium hydroxide (10% and 15%) in the treatment of molluscum contagiosum: Randomized clinical trial: Research protocol. Array [online] 2011 December [viewed 14 May 2014] Available from: doi:10.1186/1471-2334-11-278