Investigation of factors causing resistance to topical treatment and determining compliance with treatment in scabies patients

Objective: Scabies is a pruritic ectoparasitic disease. Its prevalence is increasing day by day in our country and the global disease burden is also growing. The search for treatment and high treatment failure cause patients to repeatedly visit dermatology outpatient clinics. Failure to respond to the treatments given is associated with various factors such as inappropriate use of recommended treatments, resistance or decreased sensitivity to treatments and inadequate knowledge about the transmission of the parasite. In order to reveal the factors that cause treatment failure, we organised this study in which we evaluated the patients who had previously received topical scabies treatment and who applied to us due to scabies through a questionnaire. Materials and Methods: The study was conducted by the Department of Skin and Venereal Diseases, Faculty of Medicine, Karadeniz Technical University. Between September 2022 and September 2023, patients presenting to the skin and venereal diseases outpatient clinics with complaints of pruritic rash who had received topical scabies treatment at least once in the last 6 months but did not describe improvement and whose complaints were active were included in the study after being diagnosed with scabies by history, physical examination or dermoscopically. All age groups, all ethnicities, including pregnant women and breastfeeding women, who gave consent to participate in our study were included in the study. Patients who were diagnosed with a pruritic disease other than scabies and who did not give consent to participate in the study were not included in the study. In family applications, the whole family was not included in the study, but one parent and one child were randomly included in the study to prevent statistical bias. Demographic characteristics of the individuals included in the study, history of additional chronic diseases, smoking and alcohol use, number of people living in the shelter, presence of people who go to school, use public transport and live in dormitories in the family, history of visiting with itchy family, presence of neighbour relatives who frequently visit home, characteristics related to the disease, characteristics related to previous treatments, personal hygiene and environmental hygiene characteristics were recorded in detail. Results: 489 patients were included in the study. 239 of them were female (48.9%) and 250 (51.1%) were male. The mean age of all patients was 23.94 (±22.3). 263 (53.8%) patients were in the 0-18 age range and the most affected age group. When the seasonal distribution was analysed, winter was the season in which 185 (37.8%) patients presented the most. Considering the household size of the patients, there were 296 (60.5%) people living with 4-5 members. When we questioned the living conditions of the patients and the risk of transmission, 92 (18.8%) participants had a history of staying in a dormitory and having contact with the family, 335 (68.5%) participants had a history of going to school and nursery, 314 (64.2%) participants had a history of using public transport, 225 (46%) participants had a history of being a guest or accepting itchy family as a guest, 247 (50.5%) participants had a history of frequent neighbours, relatives, relatives and playmates for children. The mean duration of pruritus was 17.5 weeks, with a minimum duration of 2 weeks and a maximum duration of 105 weeks. 430 (87.9%) participants reported nocturnal itching, 390 (79.8%) participants had a history of itching that increased with heat, 407 (83.2%) participants had a family history of itching, 425 (86.9%) participants reported itching in typical locations, and 67 (13.7%) participants had a past diagnosis of scabies. The abdomen was the most commonly involved area and was present in 399 (81.6 %) individuals. Palmoplantar involvement was present in 317 (64.8%), genital involvement in 190 (38.9%), back involvement in 119 (24.3%), leg involvement in 278 (56.9%), arm involvement in 280 (57.3%), hand-finger-wrist involvement in 362 (74%), axilla-inguinal involvement in 204 (41.7%). Excoriation was the most common with 443 (90.6%) patients, followed by tunnel with 438 (89.6%) patients. Papules were present in 229 (46,8%) patients, vesicles in 149 (30,5%) patients, eczematous rash in 133 (27,2%) patients, pustules in 65 (13,3%) patients, nodules in 60 (12,3%) patients. 270 (55,2%) patients received 1-2 treatments, 130 (26,6%) patients received 3-4 treatments, 89 (18,2%) patients received 5 or more treatments. Permethrin cream was used in 286 (58.5%) patients, permethrin lotion in 166 (33.9%) patients, Wilkinson's mixture pomade in 155 (31.7%) patients, majistral group treatments in 255 (52.1%) patients and combined treatment in 85 patients.254 (51.9%) patients applied the treatment only by themselves, 122 (24.9%) patients left the treatments on the body for an insufficient time, 98 (20%) patients did not apply the treatment everywhere, 287 (58.7%) patients applied an insufficient amount of cream, 413 (84.5%) patients did not reapply cream to the washed and wiped area and this was considered to be the most common error. In addition, 314 (64.2%) patients stated that they did not receive written instructions, 256 (52.4%) participants stated that the treatment was not explained to them in detail, and 149 (30.5%) patients stated that they used systemic or topical steroids for their rashes.57 (11.7%) patients did not apply cream to genital, 56 (11.5%) to gluteal, 54 (11%) to palmoplantar, 43 (8.8%) to axilla-inguinal, 43 (8.8%) to sub-mammary-umbilical areas. Non-scabies diagnosis was present in 119 (24,3%) patients. 85 (17.4%) patients had a history of early discontinuation of treatment. Cleanliness of clothes at appropriate temperature was missing in 111 (22.7%) patients, cleanliness of bed linen sheets at appropriate temperature was missing in 106 (21.7%) patients, cleanliness of bed, sofa, carpet and floor was missing in 168 (34.4%) patients, history of marsupial bath before treatment was missing in 138 (28.2%) patients. A total of 26 (5.3%) patients stated that they complied with all treatment recommendations. There was an error in the treatment process in 94.7% of the patients and all 26 patients who had no error had tunnels on examination. When we analysed according to age groups, we found that the group aged 65 years and over had less association with family members and more non-scabies diagnoses. In the age group of 65 years and older, washing clothes at appropriate temperature, washing bed linen at appropriate temperature, cleaning the bed-chair and space, history of marsupial bathing and the duration of the treatments in the body were found to be inadequate. In the 2-12 age group, the presence of school-going children and the presence of a history of itching in the family were more common. In the 13-64 age group, the presence of individuals living in crowded dormitories and having family contact was more prominent. In the 0-1 age group, the adequacy of the amount applied, reapplication of cream to the washed areas, application with the family, and the presence of a family history of itching were more significantly positive. In the cream form of permethrin, use with the family, adequacy of the amount applied were reported positively, whereas receiving written instructions stood out as problematic conditions. In the lotion form of permethrin, application to the whole body was more common and it was found that the treatment was not explained for a sufficient period of time. In the Wilkinson mixture pomade form, it was found that the treatments were not kept on the body for a sufficient time. In the group receiving majistral treatment, reapplication of cream to the washed and wiped areas, receiving written instructions and explaining the rules of treatment application for a sufficient time were found to be deficient. In combined treatments, it was found that the treatment was reapplied to the washed and wiped areas and the amount of cream applied was sufficient. In addition, the treatment was explained in detail and written instructions were given to this group. Receiving written instructions had a positive effect on treatment compliance at every step. Conclusion: In our study, we concluded that many mistakes are made in the topical treatment process of scabies patients and most of these mistakes are preventable mistakes. We found that the risks for transmission and the causes of treatment failures may vary according to variables such as age, drug characteristics, living areas, sociodemographic characteristics and season. With our study results, we think that the success of topical scabies treatment will be increased by revealing the causes of treatment failure and providing the correct treatment and counselling to patients, and the burden caused by this reason in increasing patient numbers will be alleviated.