Efficacy and safety of povidone iodine with dimethyl sulfoxide vs 0.05% tretinoin in treatment of molluscum contagiosum: A randomized case control study
Authors: Subodha Kumar Rai G , Parvathi Nagesha , Suresh Rangegowda , Vinay Niruvappa , Vivekananda Ittigi 
Published: August 2021

ABSTRACT Background: MC is an infection caused by a poxvirus. It is a self limiting condition, active therapy needed to prevent further spread, relieve symptoms, to prevent scarring and for cosmetic and social reasons. Methods: 40 patients were randomly divided into 2 groups; 20 each for Povidone Iodine with DMSO and 0.05% Tretinoin cream. The given medication was applied at bed time over molluscum lesions. The assessment of response and side effects were performed weekly for 4 weeks. Results: At the end of 4 weeks, the mean lesion count decreased from 6.45±3.60 SD to 4.25±3.76 SD and from 6.85±4.08 SD to 3.60±4.76 SD in patients treated with Povidone Iodine and 0.05% Tretinoin cream respectively. Conclusion: Tretinoin showed fast recovery, lesions were resolved before 4 weeks. In Povidone Iodine with DOMS showed delayed response and even some of lesion extended beyond 4 weeks but the side effect were less. Key words: MC-molluscum contagiosum.DMSO-dimethyl sulfoxide; SD-standard INTRODUCTION Molluscum contagiosum is an infection caused by a poxvirus (molluscum contagiosum virus). It is self-limited infectious dermatosis, frequent in paediatric population, sexually active adults, and immunocompromised individuals. It is caused by molluscum contagiosum virus (MCV) which is a virus of the Poxviridae family. MCV is transmitted mainly by direct contact with infected skin, which can be sexual, non-sexual, or autoinoculation [1].The lesions, known as Mollusca, are small, raised, dome shaped and usually pearly white, pink, or flesh-coloured with a dimple or pit in the centre. They often have a pearly appearance. They’re usually smooth and firm. In most people, the lesions range from about the size of a pinhead to as large as 2 to 5 millimetres in diameter. They may become itchy, sore, red, and/or swollen [2]. Mollusca may occur anywhere on the body including the face, neck, arms, legs, abdomen, and genital area, alone or in groups. The lesions are rarely found on the palms of the hands or the soles of the feet. The disease is common, with an estimated prevalence of 5–11%. The disease is rare under the age of 1 year, perhaps due to maternally transmitted immunity and a long incubation period. In hot countries where children are lightly dressed and in close contact with one another, spread within households is not uncommon. The age of peak incidence is reported as between 2 and 5 years. In cooler climates, however, spread within households is rare and infection may occur at a later age, perhaps correlated with the use of swimming pools and shared bathing facilities. A later incidence peak in young adults is attributable to sexual transmission with lesions more common in the genital area [2]. Treatment modalities that have been tried are caustic destruction by cantharidin, trichloroacetic acid, diluted liquefied phenol, Irritants like salicylic acid, adapalene, nitric oxide cream, potassium hydroxide, benzoyl peroxide, lemon myrtle oil, tea tree oil, Surgical irritation like cryotherapy, laser. Immunological modality like diphencyprone, imiquimod, interferon, cimetidine, intralesional immunotherapy and Surgical removal. All-trans-retinoic acid (tretinoin) is easily available as cream base thought to involve the induction of local irritation which damages the viral protein-lipid membrane [2]. Povidone iodine is used primarily in Dermatology as a surgical preparation, as it has been recognized as a broad-spectrum, resistance-free biocidal agent for many years. Povidone iodine also has a long track record of safety and tolerability given its extensive history of use in the operating room. Although incompletely understood, it is likely that free iodine poisons electron transport, inhibits cellular respiration, destabilizes membranes, inhibits protein synthesis, and denatures nucleic acids. Although Povidone iodine kills micro-organisms including bacteria, viruses, yeasts, molds, fungi, and protozoa, it has scarcely been used for purposes outside of skin asepsis in Dermatology. DMSO is currently FDA approved for the treatment of interstitial cystitis. DMSO is also a very effective pharmaceutical vehicle, greatly enhancing percutaneous penetration when used in combination with other substances [3]. Although it is a self limiting condition, a decision may be made in favor of active therapy to prevent further spread, relieve symptoms, to prevent scarring and for cosmetic and social reasons. The current treatment modalities include physical destruction of the lesion by curettage, cryosurgery or manual expression and topical application of caustic agents such as trichloroacetic acid, cantharidin, silver nitrate etc [4]. These therapeutic approaches have to be undertaken in a hospital setup and are not well tolerated by children owing to substantial pain and fear. In addition, these can also result in scarring and abscess formation [5]. Topical application of povidine iodine solution and 0.05% Tretinoin cream are two relatively painless modalities that have been used. Although tretinoin 0.05% cream which is commonly used, have shown different efficacy and safety profile in different studies, there are very few studies using povidone iodine and comparing the two. Hence this study was undertaken in view of comparing the safety and efficacy of the above two modalities in treating molluscum contagiosum. MATERIALS AND METHODS Double blinded randomized control study was conducted among 40 patients who attended Out Patient Department (OPD) of Dermatology Venereology and Leprosy Department, Hassan Institute of Medical Sciences Hassan, during the period of august 2019 to January 2020. Patients with Molluscum contagiosum more than 1 year of age and not taken any treatment for past 3 months were included in the study. Pregnant, lactating women, patients with more than 25 lesions, patients with lesion involving eyelid, patients with secondary infection and those who have history of hypersensitivity to Povidine iodine or Tretinoin were excluded from the study. 40 patients satisfying inclusion and exclusion criteria were recruited irrespective of sex, duration and response of disease to previous therapies. 40 patients were allocated randomly to group 1 and 2. In group 1, 20 patients were treated with povidone iodine with dimethyl sulfoxide and in group 2: 20 patients were treated with 0.05% tretinoin. A detailed history was obtained, and a thorough general, systemic and cutaneous examination was done. Information regarding age, sex, number of lesions, duration of illness, site of involvement, family history, history of atopy and previous treatment were collected. Patients were randomly divided into two groups; 20 each for povidone iodine with dimethyl sulfoxide solution and 0.05% Tretinoin cream group. Parents or guardians were advised to apply petroleum jelly around the lesions followed by application of the above medication to the centre of the lesion using a cotton swab, to be applied once every day at bed time for 4 weeks. If accidental spillage occurred, they were advised to wash the skin with water immediately. Parents were asked to report local (erythema, itching, burning, pain, erosion, crusting) and systemic (fever, flu like illness, diarrhoea, mylagia) side effects immediately. Follow up assessment was done every week for 4 weeks. At each follow up visit, clinical assessment of lesion, photographic assessment of lesion and any side effects were noted. Efficacy assessment was done by weekly examination of patient every week for 4 weeks. In each visit complete remission of number of lesions were noted in both groups and photographic assessment was done. Photographic assessment was done based on resolution of number of lesion in each follow up visit for 4 weeks. Any side effects present were noted at each visit. Statistical Analysis Data was entered in Microsoft Excel and SPSS software was used for the analysis. Results were expressed in percentages and proportions. Chi- square test, unpaired T- test, was used for analysis Ethics Statement Study was conducted after taking ethical committee clearance.