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

Prevalence and Risk Factors of Tinea Capitis Among Primary School Children in the Grand Lomé Region (Togo), 2021: A Cross-Sectional and Case-Control Study Approach

BACKGROUND

Tinea capitis is an infectious dermatosis frequent in children, causative fungi variable over time and space. The risk factors associated with this disease are still poorly understood. The objective of this study was to estimate the prevalence of tinea capitis among schoolchildren in Lomé (Togo), identify the fungal species involved and assess the associated risk factors.

PATIENTS AND METHODS

It was a cross-sectional and case-control study conducted in primary schools in Lomé from November 2020 to April 2021. All pupils presenting tinea capitis suspected lesions have been sampled, and the scraping and hair were examined by direct microscopy in KOH solution and cultured in Sabouraud dextrose agar with chloramphenicol and cycloheximide. Positive children were matched by age and sex with those without symptoms for case-control study.

RESULTS

Out of the 15,087 pupils enrolled, 465 had positive cultures for dermatophytes, corresponding to the tinea capitis prevalence of 3.08% (95% CI [2.59-3.57]). Trichophyton mentagrophytes (81.86%) and Trichophyton soudanense (13.12%) were the majors isolated dermatophytes. The risk factors were mostly living in households with domestic animals, showering less than twice a day, having a history of ringworm, having similar lesions in the same household and sharing personal hygiene items.

CONCLUSION

This study highlights the low prevalence of tinea capitis in schoolchildren in Lomé (Togo), the causative species dominated by T. mentagrophytes and emphasises the importance of environmental and behavioural factors in the mycosis transmission. Implementing preventive measures addressing the identified factors could help to reduce the prevalence of this disease.

Microsporum gypseum Infection Among Two Related Families With a Zoonotic Aspect: A Prospective Case Series

Background and purpose The Microsporum gypseum complex is a globally distributed group of geophilic dermatophytes that primarily affect animals but can also rarely cause dermatomycoses in humans. With some regional and occupational variations, tinea corporis is the most prevalent presentation of the infection. The aim of this study was to report on the diagnosis and treatment of dermatophytosis cases among related families, and their pets, from southern Saudi Arabia. Up-to-date information on dermatophytes and dermatophytosis is needed. Methods This is a prospective case series undertaken at the Dermatology Outpatient Clinic of King Khalid University, Saudi Arabia. Six patients with suspected dermatophytosis were received at our hospital in 2022 and have been followed for recovery with or without scars. Characteristics of fungal pathogens were examined phenotypically on the basis of microscopic and growth characteristics, and laboratory data were used to initiate treatment with oral fluconazole, topical terbinafine cream, or oral itraconazole. Results Clinical features and culture results confirmed tinea capitis and tinea corporis caused by M. gypseum, which was also present in a pet cat. Tinea capitis cases (n = 4) did not respond to fluconazole and terbinafine treatment, but treatment with itraconazole resulted in a full recovery. Tinea corporis cases (n = 2) were treated with terbinafine, which resulted in a full recovery within four weeks, with no signs of scarring. Conclusions M. gypseum presents with serious persistent lesions and is extremely contagious. Treatment is durable but challenging, and breaking the transmission chain is more difficult.

Determination of dermatophytes isolated from tinea capitis using conventional and ITS-based sequencing methods in Kano, Nigeria

BACKGROUND

Tinea capitis is a dermatophyte infection of the scalp and hair that affects a large number of people worldwide. The disease commonly affects children and manifests with varying degrees of hair loss, scalp inflammation, and psychosocial impact. In Nigeria, the burden of tinea capitis is worrisome affecting over 15,000,000 school-age children. Molecular techniques complement the conventional mycological examinations in laboratory diagnosis of tinea capitis. In this study, we identified dermatophytes species causing tinea capitis in Kano, Nigeria, using ITS-based nucleotide sequencing technique in addition to conventional mycological examination.

METHODS

We collected 112 samples from the scalp of children with clinically diagnosed tinea capitis at the dermatology clinic of Murtala Muhammad Specialist Hospital, Kano, between April and September 2019. The samples were processed and subjected to direct microscopy and mycological culture to isolate dermatophytes species that were identified morphologically and using ITS sequencing.

RESULTS

Out of the 112 patients investigated, the majority (59.8%) were between the ages 6 and 9 years with a mean age of 7.3 ± 1.9 years. Males (79.5%) were predominantly affected. Black dot (46.4%) was the most common clinical type of tinea capitis followed by gray patch (39.3%) and kerion (1.8%). Favus was not observed. Microsporum audouinii (45.7%) was the predominant etiologic agent followed by Trichophyton soudanense (28.6%), T. violaceum (22.9%), and T. tonsurans (2.9%).

CONCLUSION

The prominence of anthropophilic dermatophytes as the main causes of tinea capitis in our localities suggests that public health interventions to promote health education and good hygiene practices would minimize the transmission rate of tinea capitis among children in the study area.

Superficial mycoses, a matter of concern: Global and Indian scenario-an updated analysis

Superficial mycoses of skin, nails and hair are among the common fungal infections. They are caused by dermatophytes, non-dermatophyte moulds, yeasts and yeast-like fungi. Such fungal infections are widespread all over the world and are predominant in tropical as well as subtropical regions. Environmental factors, such as warm, humid and pitiable hygienic conditions, are conducive for their growth and proliferation. Although it does not cause mortality, it is known to be associated with excessive morbidity which may be psychological or physical. This affects the quality of life of the infected individuals which leads to a negative impact on their occupational, emotional and social status. Such infections are increasing on a global scale and, therefore, are of serious concern worldwide. This review article covers the global and Indian scenario of superficial mycoses taking into account the historical background, aetiological agents, prevalence, cultural and environmental factors, risk factors, pathogenesis and hygienic practices for the prevention of superficial mycoses.

A Comparative Interrupted Times Series on the Health Impact of Probiotic Yogurt Consumption Among School Children From Three to Six Years Old in Southwest Uganda

Introduction: Following a school milk feeding program in Southwest Uganda, we initiated a probiotic yogurt school feeding program in the same region in 2018. In order to investigate the potential health benefits from probiotic yogurt we conducted an observational study, where we compared the effect of the consumption of locally produced probiotic yogurt containing Lactobacillus rhamnosus yoba 2012 to milk in pre-primary schoolchildren from different schools on the occurrence of respiratory tract infections (common cold) and skin infections (e.g., tinea capitis). Method: A comparative interrupted time series over a period of 3 weeks of baseline followed by 9 weeks of 100 ml of probiotic yogurt or milk consumption for 5 days per week. In total 584 children attending five different schools were followed during consumption of probiotic yogurt and 532 children attending five other schools during consumption of milk. Incidences of respiratory tract infection symptoms and skin infection symptoms, changes in anthropometric indicators and absenteeism were recorded. Results: Over the course of the study period the incidence rate for common cold symptoms decreased faster in the yogurt group than in the milk group (p = 0.09) resulting in a final RR of 0.85 (95% CI: 0.5-1.4) at the end of the observational period. The incidence rate of skin infection related symptoms also reduced faster in the yogurt group compared to the milk group (p < 0.0001) resulting in a relative risk factor (RR) of 0.6 (CI: 0.4-0.9) at the end of the observational period. Anthropometric indicators and level of absenteeism did not show significant differences between yogurt and milk. Conclusion: Notwithstanding the observed positive trend and effect of probiotic yogurt on the incidences of common cold and skin infections, respectively, we consider the results of this comparative interrupted time series inconclusive due to differences in the recorded health parameters between the probiotic yogurt and milk control groups at base line, and fluctuations over the course of the intervention period. An improved study design, with more uniform study groups, a longer intervention period and a third control group without yogurt or milk is required to draw definitive conclusions.

Prevalence of Tinea Capitis among Children in Osogbo, Nigeria, and the Associated Risk Factors

Tinea capitis is a fungi infection of the scalp that disproportionately affects children in rural and underserved communities in Nigeria. A case-control study was conducted to identify the causative agents and factors that predispose school pupils to tinea capitis in two selected government-owned public primary schools in Osogbo, Southwestern Nigeria. A total of 230 participants were included in the study: 115 cases and 115 controls. Head scrapings were collected from pupils with suspected T. capitis lesions, viewed under Potassium Hydroxide smear microscopy and cultured in Sabouraud's Dextrose Agar (SDA) for characteristic fungal elements. A total of 105 (91%) samples were successfully cultured, of which 56% (59/105) were from male pupils. Tricophyton rubrum (34%), Tricophyton mentagrophyte (31%) and Microsporum canis (18%) were the most prevalent organisms. Other dermatophytes obtained include Microsporum nanuum (3%), Epidermophyton floccusum (6%), Tricophyton verucosum (1%), and Microsporum gypseum (8%). Pupils between the ages of 4 and 7 years had the highest distribution (67%) followed by those between the ages of 8 and 11 years (39%). Playing with animals, the sharing of combs and not bathing with soap were significantly associated with tinea capitis infection (P < 0.05) in each case. This study showed a high prevalence of tinea capitis caused by the identified dermatophytes in the area.

Single-nucleotide polymorphism in a local population of Trichophyton rubrum

Trichophyton rubrum is an important causative agent of superficial mycoses worldwide. To uncover a genetic composition of a local population of this fungus, we sequenced A7C99_6411 and A7C99_6714 loci, coding for hypothetical proteins and revealed two complex genotypes, differing by a single missense mutation in each locus. One of the two A7C99_6411/6714 genotypes was not found in tinea pedis cases and demonstrated mostly longer TRS-1 elements when compared to another genotype. Thus, we present a description of nucleotide polymorphism in protein-coding loci in T. rubrum and provide evidence for ecological preferences of T. rubrum genotypes at a local scale.

Dermatophytosis among Schoolchildren in Three Eco-climatic Zones of Mali

BACKGROUND

Dermatophytosis, and particularly the subtype tinea capitis, is common among African children; however, the risk factors associated with this condition are poorly understood. To describe the epidemiology of dermatophytosis in distinct eco-climatic zones, three cross-sectional surveys were conducted in public primary schools located in the Sahelian, Sudanian and Sudano-Guinean eco-climatic zones in Mali.

PRINCIPAL FINDINGS

Among 590 children (average age 9.7 years) the overall clinical prevalence of tinea capitis was 39.3%. Tinea capitis prevalence was 59.5% in the Sudano-Guinean zone, 41.6% in the Sudanian zone and 17% in the Sahelian eco-climatic zone. Microsporum audouinii was isolated primarily from large and/or microsporic lesions. Trichophyton soudanense was primarily isolated from trichophytic lesions. Based on the multivariate analysis, tinea capitis was independently associated with male gender (OR = 2.51, 95%CI [1.74-3.61], P<10(-4)) and residing in the Sudano-Guinean eco-climatic zone (OR = 7.45, 95%CI [4.63-11.99], P<10(-4)). Two anthropophilic dermatophytes species, Trichophyton soudanense and Microsporum audouinii, were the most frequent species associated with tinea capitis among primary schoolchildren in Mali.

CONCLUSIONS

Tinea capitis risk increased with increasing climate humidity in this relatively homogenous schoolchild population in Mali, which suggests a significant role of climatic factors in the epidemiology of dermatophytosis.

A retrospective study of cutaneous fungal infections in patients referred to Imam Reza Hospital of Mashhad, Iran during 2000-2011

Background and Purpose:

Detection of agents responsible for cutaneous mycosis may be effective in the prevention of fungal infections from environmental and animal sources. With this background in mind, in this study, we aimed to identify the distribution of cutaneous mycotic infections in patients referred to Imam Reza Hospital of Mashhad, Iran

during 2000- 2011.

Materials and Methods:

In total, 8694 patients suspected of superficial and cutaneous mycosis, referred to the Medical Mycology Laboratory of Imam Reza Hospital of Mashhad, Iran, were recruited during March 2000-2011 and were examined in terms of fungal infections.

Results:

Of 8694 suspected patients, 3804 (43.75%) cases suffered from superficial and cutaneous mycosis. In total, 1936 (50.9%) patients were male, and 1868 (49.1%) were female. Malassezia infections (58.1%), dermatophytosis (33.1%), cutaneous candidiasis (6.8%), aspergillosis (1.6%), and saprophytic cutaneous mycosis (0.4%) were the most common infections.

Conclusion:

In this study, Malassezia infections were the most common superficial and cutaneous mycoses. Therefore, it seems essential to focus on the prevention of these infections in our society.

Detection and characterization of zoonotic dermatophytes from dogs and cats in and around Kolkata

AIM

The ringworms of pet dogs, cats, and stray animals (dogs, cats, and other animals) could be a potential source of zoonotic infections causing a serious public health problem in the busy city Kolkata. The pet owners are more susceptible to get this infection from their pets, because of the close contact with them as dermatophytosis is very much prevalent in those pets. So, this study was aimed to check the prevalence of dermatophytosis in dogs, cats, and in pet owners.

MATERIALS AND METHODS

A total of 362 clinically suspected cases of dermatophytosis from dogs (123 in number), cats (202 in number), and human beings (37 in number) were collected and studied from in and around Kolkata to detect the presence of significant dermatophytes. Direct microscopy and cultural examination of the isolates were performed following standard methodology. Identification and characterization of the isolates were done by different biochemical tests.

RESULTS

Samples (n=285) having significant dermatophytic fungal infections were found to be of highest number in cats (158, 55.5%) than in dogs (108, 37.8%) and humans (19, 6.7%), respectively. The incidence of Microsporum canis (60.0%) was the highest from affecting dogs, cats, and human beings in comparison to Microsporum gypseum (22.5%), Trichophyton mentagrophytes (15.8%) and Trichophyton rubrum (1.7%). Detection of T. rubrum was only from human cases in this study, whereas the presence of rest three were slightly higher in cats than that of the dogs and humans in this present study. The incidences were higher in young animals and in humans of the age group of 21-30 years, during the rainy season (from April to August) and also in in-contact human beings.

CONCLUSION

M. canis was the most commonly pathogen among all causing dermatophytosis in animals and also in the pet owners. M. gypseum and T. mentagrophytes were other pathogens associated with these infections. These infections were more prevalent in the rainy seasons and in in-contact human patients or pet owners.

Dermatophytes and other associated fungi in patients attending to some hospitals in Egypt

Dermatophytes are keratinophilic fungi that infect keratinized tissues causing diseases known as dermatophytoses. Dermatophytes are classified in three genera, Epidermophyton, Microsporum, and Trichophyton. This investigation was performed to study the prevalence of dermatomycosis among 640 patients being evaluated at the dermatology clinics at Kasr elainy, El-Husein and Said Galal hospitals in Cairo and Giza between January 2005 and December 2006. The patients were checked for various diseases. Tinea capitis was the most common clinical disease followed by tinea pedis and tinea corporis. Tinea cruris and tinea unguium were the least in occurrence. Tinea versicolor also was detected. The most susceptible persons were children below 10 years followed by those aged 31-40 years. Unicellular yeast was the most common etiological agent and T. tonsuranswas the second most frequent causative agent followed by M. canis.

Epidemiology of tinea capitis among school-age children in Meiganga, Cameroon

Tinea capitis (TC) commonly called scalp ringworm is a worldwide concern and a public health problem in Africa. This study aimed at determining the epidemiologic profile of TC among school-aged children in the savanna zone of Cameroon. All children present at school during this study period, August 2011-July 2012, were examined for signs suggestive of TC. Children not registered at school were excluded from the study. Pathologic specimens were taken from suspected head lesions and cultured. Amongst the 4601 children, average age 10.7±0.16 years, 377 presented with suggestive TC lesions giving a prevalence of 8.1%. The proportion of boys with TC was (63.7%) higher than in girls (36.3%) (P≤0.05). TC manifestations varied; small plaques of alopecia 59.26% were the most frequent. Communal living was the most incriminated risk factor. Three hundred and thirty six isolates were obtained in culture. The prevalence was significantly higher (P<0.05) in age range between 8 and 12 years, followed by that between 13 and 15. The most prevalent isolate was T. soudannense 56.8%, followed by T. rubrum 29.2%. Only 6.0% of the isolates belonged to the genus Microsporum.

Onychomycosis in Cameroon: a clinical and epidemiological study among dermatological patients

BACKGROUND

There are currently no studies on epidemiology and clinical aspects of nail fungal infections in the general population of Cameroon.

PATIENTS AND METHODS

Two series of patients observed at a hospital dermatological service of Yaoundé and in a volunteer service of Douala were evaluated. All the patients, regardless of the reason for the consultation, were examined by an expert dermatologist to discover signs of onychomycosis. Patients with suspected nail lesions underwent mycological examination according to the standard techniques.

RESULTS

Among 590 subjects (317 males and 273 females), aged 16-83 years, onychomycosis was mycologically confirmed in 52 cases (8.8%). The infection was most common in the fifth decade. Fingernails were affected in 12 cases, toenails in 30 cases, and both fingernails and toenails in 10 cases. Dermatophytes were isolated in 57.7% of cases, the most common species being Trichophyton rubrum (16 cases) and Trichophyton violaceum (eight cases). Non-dermatophytic mould, including Aspergillus spp., Fusarium spp., and Neoscytalidium dimidiatum, was found in 10 cases. Onychomycosis was more common in patients from low social-economic classes.

CONCLUSIONS

This is the first investigation dealing with onychomycosis in Cameroon. These data may be useful for future research and in the development of preventive and educational strategies.

Prevalence and causative fungal species of tinea capitis among schoolchildren in Gabon

Tinea capitis is endemic among schoolchildren in tropical Africa. The objective was to determine the prevalence of symptomatic tinea capitis in schoolchildren in Gabon. A cross-sectional study was conducted with 454 children aged 4-17 years, attending a rural school and an urban school. The diagnosis of tinea capitis was based on clinically manifest infection, direct microscopic examination using 20% potassium hydroxide (KOH) solution and fungal culture. Based on clinical examination, 105 (23.1%) of 454 children had tinea capitis. Seventy-four (16.3%) children were positive by direct examination (KOH) and/or fungal culture. The prevalence of tinea capitis depended on the school studied and ranged from 20.4% in the urban school with a higher socioeconomic status to 26.3% in the rural school with a lower socioeconomic status. Similarly, the spectrum of causative species varied between the different schools. Taken the schools together, Trichophyton soudanense (29.4%) was the most prominent species, followed by Trichophyton tonsurans (27.9%) and Microsporum audouinii (25.0%). Clinically manifest tinea capitis is endemic among schoolchildren in the Lambaréné region in Gabon. The prevalence of tinea capitis and the causative species depended on the type of school that was investigated.

Occidiofungin, a unique antifungal glycopeptide produced by a strain of Burkholderia contaminans

Bacterial strain Burkholderia contaminans MS14 was isolated from soil that suppressed brown patch disease of lawn grass. An antifungal compound was purified from the liquid culture of this bacterium. In this study, complete covalent structures of two purified closely related antifungal compounds were determined by the experiments of TOCSY, NOESY, ROESY, 13C HSQC 2D NMR, and ESI-MS and GC. The analysis of monoisotopic masses of the purified preparation indicated the presence of two related compounds with masses determined to be 1199.543 and 1215.518 Da; the difference corresponds to the mass of an oxygen atom. GC analysis identified a xylose sugar attached to the antifungal compound. NMR experiments revealed that the compound is cyclic and composed of eight amino acids, two of which are beta-hydroxy derivatives of Tyr and Asn, and one being a novel amino acid. The novel amino acid serves as the scaffold for the attachment of the xylose and a short acyl chain. The spectrum and concentration of antifungal activity were determined using a microtiter plate assay. The antifungal compound demonstrated potent antifungal activities against a broad panel of fungal plant and animal pathogens, as well as two Pythium spp. Microscopic observations showed that the antifungal compound disrupts normal membrane morphology. The cells fill with large inclusion bodies and the membrane becomes irregularly shaped and swollen following the exposure to subinhibitory concentrations of the antifungal compound. Our data support the identification of a novel fungicide and the compound has been named occidiofungin, meaning fungal killer.

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.