Dermatophytosis in Tulugudu Island, Ethiopia

Predominance of Trichophyton soudanense as Agent of Dermatophytoses in Cape Verdean School-Age Children

Dermatophytoses are infectious skin diseases of public health importance because of their transmissibility and high prevalence, especially among children. This is the first study aiming to estimate and report the burden of dermatophytoses on school-age children on the island of Santiago in Cape Verde, an African country that is an archipelago. A total of 249 students attending the afternoon shift of three elementary schools in the city of Achada Igreja were examined. Of these, 60 had suspected lesions of dermatophyte infection. However, from the samples collected from these 60 students, including hair, nails, and skin scrapings, only 18 dermatophyte isolates were obtained, corresponding to a point prevalence of 7.2%. Morphological species identification demonstrated three different species: Trichophyton soudanense, Trichophyton rubrum, and Trichophyton violaceum; re-identification by sequencing the internal transcribed spacer (ITS) 1 and 2 regions of ribosomal DNA, and the 5.8S rDNA encoding gene (ITS-5.8S region), revealed T. soudanense as the most prevalent species, with only one case of T. rubrum. This is the first epidemiological data describing dermatophytoses and dermatophytes in Cape Verde among school-age children on one of the archipelago islands. It reinforces the need of using culture and accurate identification methodologies when gathering epidemiological data on dermatophytoses.

Dermatophytosis and the associated risk factors among primary school children in southern and central Côte d'Ivoire

BACKGROUND

Dermatophytosis, particularly the subtype tinea capitis, is common among African children; however, the risk factors associated with this condition are poorly understood.

OBJECTIVES

This study aimed to determine the factors associated with tinea capitis and the prevalence rate of other dermatophytoses among primary school students in the rural and urban areas of the southern and central Côte d'Ivoire.

PATIENTS AND METHODS

The study was carried out in seven towns of Côte d'Ivoire from October 2008 to July 2009, among 17,745 children aged 4-17 years and attending urban and rural primary schools; a complete physical examination of the skin and appendages, including nails and hair, was performed by the physicians. Direct microscopic examination using 30% potassium hydroxide solution and culture on Sabouraud's dextrose agar supplemented with 0.5 g/L chloramphenicol and 0.4 g/L actidione was performed during sampling.

RESULTS

For the 17,745 children clinically examined, 2645 exhibited symptoms suggestive of tinea capitis. Positive cultures for dermatophytes were found in 2635 patients, and the overall prevalence rate of tinea capitis was 14.8%. The following factors, age, sex, pets at home, number of bathing daily, sharing of sponges, combs and towels and hair length, were statistically associated with tinea capitis (p < .001). In addition to tinea capitis, other superficial fungal infections were identified among these children. These included tinea corporis (0.9%), tinea unguium (0.6%) and pityriasis versicolor (0.4%).

CONCLUSION

Tinea capitis is common among pupils in rural southern and central Côte d'Ivoire, especially in young boys.

Dermatophytosis and its risk factors among children visiting dermatology clinic in Hawassa Sidama, Ethiopia

Dermatophytosis represents one of the common fungal diseases that attack the skin, hair and nail of human beings worldwide. It causes chronic morbidity in children and the condition is more common, in developing countries. The study aimed to determine dermatophytosis and its associated factors among children in Hawassa Sidama, Ethiopia April 2021-October 2021. A cross-sectional study was conducted on children suspected of cutaneous fungal infections. Data were surveyed based on a semi-structured questionnaire. Standard laboratory methods were used to identify the dermatophytes. The data entry and analysis were conducted with SPSS version 26. The Chi-square test was used to check the predictor and a p-value < 0.05 was taken as a significant value. A total of 83 study subjects included in the study in which all 83 (100%) patients were positive for fungal elements (hyphae/and spores) in microscopy, of this 81 (97.6%) yielded growth on culture. Hair scalps 75 (90.4%) were the dominant among the case. Trichophyton 52 (62.6%) was the dominant aetiology followed by Microsporum 22 (26.6%). Intervention measures to tackle dermatophytosis should emphasis on tinea capitis among 6-10 years old children with history of recent migration by raising awareness of communities through health extension programs.

Phenotypic Characterization of Enzymatic and Non-enzymatic Virulence Factors in Etiopathogenesis and Evolution of Drug Resistance among Dermatophytes

The virulence factors of dermatophytes play a vital role in the etio-pathogenesis and emergence of drug resistance. Regular surveillance is essential for constant monitoring of association of virulence factors in the emergence of drug resistant isolates and to guide proper therapeutic strategies to combat infections due to drug resistant isolates of dermatophytes. The aim of this study is to isolate and identify various enzymatic and non-enzymatic virulence factors of dermatophytes isolated from clinically suspected cases of dermatophytosis attending the dermatology outpatient clinic. From 30 clinical samples received from department of Dermatology to the department of Microbiology during the study period July to December 2019, KOH mount and fungal culture was done and only the isolates which grew dermatophytes were used for detecting virulence factors using standard methods. Among 30 affected patients, 13 were male (43.3%) and 17 were female (56.7%) with age range of 13 to 60 years. Skin sample yielded positive growth in 96.6% of the cases. Out of 30 samples, 6 samples were positive for Trichophyton mentagrophytes. Tinea corporis was the common manifestation which yielded positive growth. Female predominance was seen. Male predominance was seen in younger age group while females were more commonly affected in older age group. Adolescents were commonly affected age group (40%). Then people between age 41-50 (middle age group) were mostly affected. The six Trichophyton mentagrophytes were found to have enzymatic and non- enzymatic virulence factors. All the virulence factors included in the study were present in Trichophyton mentagrophytes.

Estimation of the burden of tinea capitis among children in Africa

Tinea capitis is a common and endemic dermatophytosis among school age children in Africa. However, the true burden of the disease is unknown in Africa. We aimed to estimate the burden of tinea capitis among children <18 years of age in Africa. A systematic review was performed using Embase, MEDLINE and the Cochrane Library of Systematic Reviews to identify articles on tinea capitis among children in Africa published between January 1990 and October 2020. The United Nation's Population data (2019) were used to identify the number of children at risk of tinea capitis in each African country. Using the pooled prevalence, the country-specific and total burden of tinea capitis was calculated. Forty studies involving a total of 229,086 children from 17/54 African countries were identified and included in the analysis. The pooled prevalence of tinea capitis was 23% (95% CI, 17%-29%) mostly caused by Trichophyton species. With a population of 600 million (46%) children, the total number of cases of tinea capitis in Africa was estimated at 138.1 (95% CI, 102.0-174.1) million cases. Over 96% (132.6 million) cases occur in sub-Saharan Africa alone. Nigeria and Ethiopia with the highest population of children contributed 16.4% (n = 98.7 million) and 8.5% (n = 52.2 million) of cases, respectively. Majority of the participants were primary school children with a mean age of 10 years. Cases are mostly diagnosed clinically. There was a large discrepancy between the clinical and mycological diagnosis. About one in every five children in Africa has tinea capitis making it one of the most common childhood conditions in the region. A precise quantification of the burden of this neglected tropical disease is required to inform clinical and public health intervention strategies.

Belgian National Survey on Tinea Capitis: Epidemiological Considerations and Highlight of Terbinafine-Resistant T. mentagrophytes with a Mutation on SQLE Gene

Background: In this last decade, a huge increase in African anthropophilic strains causing tinea capitis has been observed in Europe. The Belgian National Reference Center for Mycosis (NRC) conducted a surveillance study on tinea capitis in 2018 to learn the profile of circulating dermatophytes. Methods: Belgian laboratories were invited to send all dermatophyte strains isolated from the scalp with epidemiological information. Strain identification was confirmed by ITS (Internal Transcribed Spacer) sequencing. Mutation in the squalene epoxidase (SQLE) gene was screened by PCR. Results: The main population affected by tinea capitis was children from 5–9 years. Males were more affected than females. The majority of the strains were collected in the Brussels area followed by the Liege area. Among known ethnic origins, African people were more affected by tinea capitis than European people. The major aetiological agent was Microsporum audouinii, followed by Trichophyton soudanense. One strain of Trichophyton mentagrophytes has been characterized to have a mutation on the squalene epoxidase gene and to be resistant to terbinafine. Conclusions: African anthropophilic dermatophytes are mainly responsible for tinea capitis in Belgium. People of African origin are most affected by tinea capitis. The monitoring of terbinafine resistance among dermatophytes seems necessary as we have demonstrated the emergence of resistance in T. mentagrophytes.

Host- and pathogen-dependent susceptibility and predisposition to dermatophytosis

Dermatophytes are a highly specialized group of keratinophilic and keratinolytic filamentous fungi causing a ringworm disease called dermatophytosis or superficial mycoses. Although dermatophyte infections do not threaten the host's life, they lower its quality in humans by causing discomfort related to cosmetic problems and through their epidemiological significance, whereas in farm animals they are responsible for economic losses and constitute a source of the spread of spores. Evidence from countless observational studies that have been conducted over the last 90 years indicates that dermatophytes infect humans of every age, race, gender and socioeconomic status with strikingly high rates, as well as both farmed and wild animals in various health conditions and with various epidemiological statuses. However, the prevalence of superficial fungal infections is highly variable, since it depends on several parameters associated with the infected individual and the dermatophyte, their mutual interactions, and epidemiological and geographical factors. The curious disparity in dermatophyte infection patterns has prompted many investigators to search for a link between the host, the host's predispositions and susceptibility to the disease, and the dermatophyte species and virulence. Thus, the question arises as to whether, in addition to the generally recognized factors predisposing hosts to diseases, there are some other predispositions to dermatophyte infections in a species-specific host. In this review, we describe recent findings about the mechanism of dermatophyte infections, focusing on the adaptation of the fungi to the host and conditions predisposing each side to the disease.

Dermatophytosis: Prevalence of Dermatophytes and Non-Dermatophyte Fungi from Patients Attending Arsho Advanced Medical Laboratory, Addis Ababa, Ethiopia

BACKGROUND

Dermatophytosis is a disease of major public health problem around the globe causing a considerable morbidity.

OBJECTIVE

To study the prevalence of dermatophytosis and the spectrum of fungi implicated in causing the infection.

METHODS

Nail, skin, and scalp scrapings were collected from 318 patients and were used for microscopy and culture study. Fungal pathogens were identified by studying the macroscopic and microscopic characteristics of their colonies.

RESULT

Tinea capitis was the predominant clinical manifestation consisting of 48.1% of the cases. Among 153 patients with tinea capitis, 73.2% were in the age group of 1-14 years. Of 318 study participants, 213 (67.98%) were found to be positive for dermatophytosis microbiologically. Out of 164 fungal isolates, 86 were dermatophytes and 78 were non-dermatophyte fungi. Among 86 dermatophytes, T. violaceum represented 38.4% of dermatophyte isolates and 89.7% of the isolates were recovered from tinea capitis. Of 76 non-dermatophyte molds, Aspergillus spp., Scytalidium dimidiatum, and Cladosporium spp. were the most common isolates, respectively.

CONCLUSIONS

Failure to detect or isolate fungal pathogens in a large number of clinical samples revealed the limitation of clinical diagnosis in differentiating dermatophytosis from other skin infections demonstrating that clinical diagnosis should be coupled with laboratory methods. Recovery of large number of non-dermatophyte fungi along with dermatophytes in our study showed that non-dermatophyte fungi are emerging as important causes of dermatophytosis, warranting the implementation of intensive epidemiological studies of dermatophytosis across the country.

Dermatophytes and dermatophytosis in the eastern and southern parts of Africa

Dermatophytosis is currently a disease of global importance and a public health burden. It is caused by dermatophytes, which attack and grow on dead animal keratin. Dermatophytes belong to three genera, namely, Epidermophyton, Microsporum, and Trichophyton. The predominant clinical forms and causative agents vary from one region of the world to another. Poor socioeconomic status, high population densities, and poor sanitary conditions are some of the factors responsible for the high prevalence of dermatophytosis in many developing countries, which include countries in southern and eastern Africa, the focus of this review. To the best of our knowledge, there is currently no review article on published findings on dermatophytosis in the eastern and southern parts of Africa. This information will be of interest to the medical and research community since the world has become a global village. This review covers published research findings in eastern and southern regions of Africa until this date. The countries covered in the current review include Kenya, Ethiopia, Tanzania, South Africa, Mozambique, Madagascar, Malawi, Rwanda, Burundi, Uganda, Zambia, Zimbabwe, and Botswana. T. violaceum is the most common human etiological agent in all the countries under review with prevalence ranging from 56.7% to 95%, except for Madagascar (M. langeronii, reclassified as M. audouinii), Uganda (M. gypseum) and Malawi (M. audouinii). Tinea capitis was the most clinical type, followed by tinea corporis. Etiological agents of animal dermatophytoses were variable in the countries where they were reported. Major risk factors for dermatophytoses are age, climatic, and socioeconomic factors.

Genetic Predictors of Susceptibility to Dermatophytoses

Countless observational studies conducted over the last century reveal that dermatophytes infect humans of every age, race, gender, and socioeconomic status with strikingly high rates. The curious disparity in dermatophyte infection patterns observed within and between populations has led countless investigators to explore whether genetics underlie a susceptibility to, or confer protection against, dermatophyte infections. This paper examines the data that offer a link between genetics and dermatophytoses and discusses the underlying mechanisms that support these observations.

Prevalence of Dermatophytic Infection and the Spectrum of Dermatophytes in Patients Attending a Tertiary Hospital in Addis Ababa, Ethiopia

Background. Dermatophytosis is common worldwide and continues to increase. Objective. This study was undertaken to determine the prevalence of dermatophytosis and the spectrum of ringworm fungi in patients attending a tertiary hospital. Methods. Samples were collected from 305 patients. A portion of each sample was examined microscopically and the remaining portion of each sample was cultured onto plates of Sabouraud's dextrose agar containing chloramphenicol with and without cycloheximide. Dermatophyte isolates were identified by studying macroscopic and microscopic characteristics of their colonies. Result. Of 305 samples, fungi were detected in 166 (54.4%) by KOH of which 95 were dermatophytes while 242 (79.4%) samples were culture positive of which 130 isolates were dermatophytes. Among dermatophyte isolates T. violaceum was the most common (37.7%) cause of infection. Tinea unguium was the predominant clinical manifestation accounting for 51.1% of the cases. Patients with age group 25–44 and 45–64 years were more affected. T. violaceum was the most common pathogen in tinea unguium and tinea capitis, whereas T. mentagrophytes was the most common pathogen in tinea pedis. Conclusion. Further intensive epidemiological studies of ring worm fungus induced dermatophytosis which have public health significance are needed.

Griseofulvin Only Modestly Diminishes Persistence of Trichophyton tonsurans on the Scalp of Carriers

OBJECTIVES

Using genetic strain typing, we previously identified a high rate of T. tonsurans carriage among preschool-aged children attending an urban daycare center. No treatment was provided as part of the observational study; however, children when symptomatic were treated in accordance with daycare policies. This retrospective investigation examines antifungal drug therapy received during the previous investigation and characterizes the impact of treatment on persistence of the fungus on the scalp.

METHODS

Children in whom serial typeable isolates of T. tonsurans were recovered were eligible for evaluation. Clinic charts were reviewed and dispensing records obtained from the primary pharmacies serving the daycare. Infection patterns were examined before and after treatment.

RESULTS

We identified 72 dispensing records for 53 children, all of whom received griseofulvin. Nine children could not be evaluated because treatment was coincident with their last study visit. Thus, 63 treatment events in 44 children with 331 discrete infection events remained. After a single course of griseofulvin, 22.7% of children became culture negative, 6.8% acquired another strain of T. tonsurans and, 70.5% remained persistently positive with the same strain carried prior to treatment. Among those receiving a second course of therapy, 54% remained positive and the cumulative percent of children that became culture negative increased to 36.4%. If children subsequently acquiring a different strain are considered together with those that became culture negative, cumulative strain clearance was observed in 43% of children. Neither the griseofulvin dose nor the duration of time over which children were infected prior to treatment differed between those that remained positive and those that became negative.

CONCLUSIONS

Griseofulvin eradicates dermatophyte scalp carriage in less than one-half of preschool-aged children receiving between one and four 4-week courses of the drug.

Epidemiology of dermatophyte infections in Stockholm, Sweden: a retrospective study from 2005-2009

Dermatophytic infections are common worldwide but the distribution of dermatophyte species varies among geographical areas and changes over time. The aim of this study was to determine the epidemiologic profile of dermatophytosis in Stockholm, Sweden. Laboratory records comprising direct microscopy and culture results of 37,503 specimens from skin, hair and nail scrapings collected from January 2005 through December 2009 were retrospectively analyzed in the mycology laboratory at Karolinska University Hospital. Onychomycosis had, over time, the highest overall prevalence of 14.1%, followed by tinea pedis (4.4%). Trichophyton rubrum was the predominant pathogen isolated from these cases (83.2%), followed by T. mentagrophytes (7.4 %). In contrast, T. violaceum and T. soudanense accounted for 81.6% of the isolates from patients with tinea capitis.

Tinea capitis among children in the Columbus area, Ohio, USA

Tinea capitis is a fungal infection of the hair follicles of the scalp. In the US, the most common organisms have traditionally been Trichophyton tonsurans, and occasionally Microsporum canis. This study was designed to examine patterns of organisms causing tinea capitis and determine factors associated with infection. A retrospective database analysis was conducted to locate records of patients with tinea capitis from May 2001 to May 2006 at Nationwide Children's Hospital in Columbus, OH. Descriptive statistics, frequency analysis, chi-squared test, and Student's t-test were performed to evaluate types of causative organisms and associated patient characteristics. One hundred and eighty-nine charts of patients with a positive scalp culture for tinea capitis were located. Trichophyton tonsurans (88.9%) was the foremost causative agent followed by Trichophyton violaceum (4.2%). Tinea capitis was more prevalent among African Americans and was more common in urban areas (P < 0.05). Children of African descent inhabiting urban settings were most vulnerable to tinea capitis. The most common organism isolated in this retrospective study was T. tonsurans. Trichophyton violaceum and Trichophyton soudanense were also isolated, which are not commonly reported causes of tinea capitis in the US.

Dermatophyte infections in Cairo, Egypt

In this study, we examined dermatophyte infections in patients referred to the Department of Dermatology, EL-Houd El-Marsoud Hospital, Cairo, during March 2004 to June 2005. Of 506 patients enrolled in this investigation, 403 (79.6%) were clinically diagnosed as having dermatophytoses (age range 6-70 years; males 240; females 163). Species identification determined by observation of their macroscopic and microscopic characteristics was complemented with sequencing of the internal transcribed spacer ITS1-5.8S-ITS2 rDNA region. The most common dermatophyte infection diagnosed was tinea capitis (76.4%), followed by tinea corporis (22.3%) and tinea unguium (1.2%). The most frequently isolated dermatophyte species was Trichophyton violaceum, which accounted for most (71.1%) of all the recovered dermatophytes, followed by Microsporum canis (21.09%), Trichophyton rubrum (6.2%), and Microsporum boullardii (0.49%); both Epidermophyton floccosum and Trichophyton tonsurans were each only rarely isolated (0.24%).

Epidemiology of dermatophytoses in a rural community in Eastern Nigeria and review of literature from Africa

A total of 4,287 primary school children, comprising 1,740 males and 2,547 females in Arochukwu local government area of Abia state Nigeria were examined for clinical signs of dermatophytoses. About 873 (20.4%), consisting of 505 males and 368 females had lesions consistent with dermatophytoses. The disease was more prevalent in males (29%) than females (14.4%) in a ratio of approximately 2:1 (P < 0.05). The infection rate increased from 16.8% in the 4-6 year age group to a peak of 28.1% in the 10-12 year age bracket and dropped sharply to 5.6% in the 16-18 year group. The highest prevalence (39%) was observed among males aged 10-12 years while females 16-18 years had the lowest prevalence (2.5%). Tinea capitis was the predominant clinical type of dermatophytoses, and occurred in 13.7% of the total population studied and 67% of lesion positive cases. Trichophyton soudanense and Trichophyton tonsurans the predominant aetiological agents of dermatophytoses with a prevalence of 26.2% and 21.6%, respectively. Others include Trichophyton mentagrophytes (18.8%), Epidermophyton floccosum (8.3%), Microsporum audouinii (6.4%), Microsporum gypseum (6.0%), Trichophyton rubrum (5.5%) and Microsporum ferrugineum (7.3%), which was isolated for the first time in Nigeria.

Multilocus genotyping identifies infections by multiple strains of Trichophyton tonsurans

Acquisition of multiple genetic strains of a single dermatophyte species should not be unexpected in areas of high endemicity, and yet multistrain infections are infrequently reported. This communication details mixed Trichophyton tonsurans infections and highlights the need to confirm the presence of multiple strains in a clinical single isolate by use of a multilocus approach.

White variants of Trichophyton violaceum isolated in Ethiopia

Certain dermatophytes are geographically restricted and endemic in particular parts of the world, while other species may have a sporadic but worldwide distribution. Trichophyton violaceum is one of the most common dermatophytes causing tinea capitis, and is the predominant cause of tinea in Africa, South America and the Indian subcontinent. Among 1187 dermatophyte isolates collected from Ethiopian patients with various types of tinea, 32 isolates had uncharacteristic phenotypic features. Based on conventional methods complemented by sequence analysis of the rDNA ITS2 region, these isolates were identified as white variants of T. violaceum. This is the first time that white isolates of T. violaceum have been identified in Ethiopia.

Prevalence of tinea capitis in Ethiopian schoolchildren

The prevalence of dermatophytosis and the spectrum of dermatophyte species were determined in children attending two schools in Addis Ababa, Ethiopia. Demographic and clinico-dermatological data were collected. Specimens were taken for microscopy and culture from all suspected lesions. Dermatophyte species were identified by morphology and biochemical tests, supplemented by sequencing of the rDNA ITS 2 region in selected isolates. From the Biruh Tesfa Elementary School (BTES) 824 students, and from Mount Olive Academy (MOA) all 124 students, were included. In BTES 513 (62.3%) students were clinically diagnosed with dermatophytosis, 463 (90.3 %) of them with tinea capitis. In 200 consecutive samples from BTES, and in 66 from MOA, 75 and 62%, respectively, contained fungal elements at microscopy. From BTES, 163/496 (33%) samples were culture-positive, of which 149 (91.4%) grew with dark purple colonies identified as Trichophyton violaceum, while 244 (49.4%) samples were contaminated. A few strains grew slowly developing white to cream colonies, two were identified as T. verrucosum, and 12 as white T. violaceum. From MOA 44 (66.7%) of samples were culture-positive, 38 (87%) were identified as T. violaceum, and one (2.3%) as T. verrucosum, while 33% showed no growth. Four white isolates of T.violaceum were confirmed by DNA-sequencing. Dermatophytosis was thus diagnosed in 55-62% of children screened at two schools of different socioeconomic standards in the Ethiopian capital. Trichophyton violaceum constituted 87-90% of all isolates. White variants of T. violaceum were diagnosed in 16 cases.