| Literature DB >> 36247346 |
Vidya Laxmi Jaishi1, Ranjana Parajuli2, Pragyan Dahal2, Roshani Maharjan1.
Abstract
Fungal infections of hair, nail, and skin are common worldwide and tend to increase. The present study was conducted to determine the prevalence of dermatomycoses, estimate the efficiency of rapid potassium hydroxide (KOH) wet-mount, and observe the hygienic status and the predisposing risk factors. Altogether 115 samples (nail = 77, skin = 30, and hair = 8) were obtained in a duration of December 2019 to June 2020 at Grande International Hospital, Nepal. The samples were examined by KOH wet-mount microscopy and further processed for culture. The dermatophyte test medium (DTM) was used to isolate dermatophytes separately. The fungal colonies obtained in SDA, SDA with cycloheximide/chloramphenicol and dermatophyte medium were subjected to lactophenol cotton blue (LPCB) reagent to study fungal morphology. The yeast colonies grown on SDA were subjected to Gram staining, germ-tube tests, and biochemical tests for identification. CHROMagar was used to distinguish different Candida species based on its pigment production in the medium. Various factors (age, sex, occupation, and hygiene condition) were analyzed which were associated with mycological infection. Out of 115 samples, the presence of fungal elements was detected in 20 samples by KOH. Nondermatophyte molds were the most isolated fungus in nails, skin, and hair, followed by yeast and dermatophytes, respectively. Dermatomycosis molds were the most common causative agents with 22 (14.7%) cases, followed by yeasts with 6 (5.21%) cases. Candida albicans was isolated from 5 (4.3%) cases, whereas Rhodotorula species accounted for a single (0.8%) case. Dermatophytes were isolated from 5 (4.3%) cases. Among them, n = 4(3.4%) cases revealed Trichophyton rubrum and Trichophyton mentagrophytes was isolated from single (0.8%) case. The most isolated nondermatophyte mold that follows criteria as a pathogen in our study was Cladosporium species 6 (25%) out of 27 total fungal isolates. Poor hygiene and sweating were found to be statistically significant (P < 0.05) in fungal cases detected by both KOH and culture. Dermatophytes and nondermatophyte fungi were emerging as important causes of fungal infection. Both direct microscopy and culture followed by LPCB together were vital tools for the diagnosis of fungal infections.Entities:
Year: 2022 PMID: 36247346 PMCID: PMC9553492 DOI: 10.1155/2022/3088681
Source DB: PubMed Journal: Interdiscip Perspect Infect Dis ISSN: 1687-708X
Demographic characteristics of study population.
| Characteristics | Patients |
|---|---|
| Mean age in years (SD) | 47 ± 8.5 |
| Gender | |
| Males (%) | 68 (59.1) |
| Females (%) | 47 (40.6) |
| Occupations | |
| Livestock farming (%) | 9 (7.8) |
| Poultry farming (%) | 10 (8.6) |
| Crop farming (%) | 6 (5.2) |
| Others | 90 (78.2) |
| Total (%) | 115 (100) |
Age and sex-wise distribution of participants based on clinical manifestation.
| Age (in years) | Male | Female | Total (%) | Clinical manifestation |
|---|---|---|---|---|
| ≤10 | 1 | 1 | 2 (1.7) | Tinea incognita |
| 11–20 | 7 | 5 | 12 (9.5) | Tinea faciei |
| 21–30 | 5 | 3 | 8 (6.9) | Tinea corporis |
| 31–40 | 10 | 7 | 17 (14.7) | Tinea cruris |
| 41–50 | 19 | 15 | 34 (29.5) | Tinea corporis |
| 51–60 | 13 | 6 | 19 (16.5) | Tinea unguium |
| 61–70 | 11 | 9 | 20 (18.2) | Tinea unguium |
| 71–80 | 1 | 1 | 2 (1.7) | Tinea capitis |
| 81–90 | 1 | 0 | 1 (0.8) | Tinea manuum |
| Total | 68 | 47 | 115 (100) |
Figure 1KOH wet-mount of skin sample showing hyaline, branched, aseptate fungal hyphae.
Figure 2Budding yeast cells with pseudohyphae observed in Gram staining.
Figure 3Aspergillus flavus showing structural radiated biseriate head in LPCB stain.
Figure 4Fusiform to sickle shaped macroconidia of Fusarium species in LPCB stain.
Figure 5Alternaria spp (macroconidia: Obclavate, obpyriform, often with short conical or cylindrical beak, pale brown) in LPCB stain.
Direct microscopic examinations results of nondermatophytes mold with colony characteristics in SDA with their LPCB identification.
| KOH wet-mount results/Direct microscopic examination | Number of fungal elements observed in direct KOH wet-mount. | Fungal colony morphological characteristics in SDA | LPCB identification |
|---|---|---|---|
| Dark, branched septate fungal hyphae seen. | 6 | Olivaceous-brown to blackish-brown colonies suede-like to floccose turning later into powdery colony due to the production of abundant conidia. |
|
| Hyaline, branched septate fungal hyphae seen. | 2 | Green, velvety, wrinkled colony. |
|
| Hyaline, branched septate fungal hyphae with acute angle branching seen. | 2 | Granular, flat colonies with radial grooves, yellow at beginning later quickly becoming bright to dark yellow-green. |
|
| Hyaline, branched septate fungal hyphae with acute angle branching seen. | 2 | Pale, bright-colored, fast-growing colonies with a cottony aerial mycelium. No pigmentation was observed in reverse side. |
|
| Brown branched septate fungal hyphae seen. | 1 | Woolly to velvety colony, suede like and olivaceous to black in obverse and reverse side. |
|
| Dark brown pigmented, branched septate fungal hyphae seen. | 1 | Dark brown and velvety, loose cottony at the center with black pigmentation in reverse side. |
|
| Dark, branched septate fungal hyphae seen with branched chains of large conidia. | 1 | Colonies appeared black to olivaceous-black or grayish and has suede-like to floccose appearance. |
|
| Hyaline, branched aseptate fungal hyphae seen. | 1 | White to grayish brown, fast-growing colonies resembling salt and pepper appearance. |
|
| Plenty of budding yeast cells seen. (Arthroconidia was observed in LPCB mount and Gram staining prepared from culture) | 3 | Soft, smooth, mucoid, and orange pigmented colony in the obverse side. |
|
| White, small, creamy, and pasty colony |
|
Evaluation of KOH preparation with culture for the detection of fungal infection.
| Test | Culture | |||
|---|---|---|---|---|
| KOH | Positive | Negative | Total | |
| Positive | 20 (TP) | 6 (FP) | 26 | |
| Negative | 13 (FN) | 76 (TN) | 89 | |
| Total = | Total = | Total = | ||
| Sensitivity | 71.7%, 95% CI (56.5% to 84.0%) | |||
| Specificity | 93.1%, 95% CI (85.7% to 97.4%) | |||
| PPV | 84.6%, 95% CI (71.3% to 92.4%) | |||
| NPV | 86.3%, 95% CI (79.8% to 90.9%) | |||
| Accuracy | 85.8%, 95% CI (78.7% to 91.2%) | |||
| Kappa value | 0.5, 95% CI (0.7 to 0.4) | |||
|
| <0.001 | |||
Abbreviations. TP = true positive; FP = false positive; TN = true negative; FN = false negative.
Figure 6Frequency of fungal isolates from nail, skin, and hair amongst culture-positive cases.
Distribution of fungal isolates concerning clinical manifestation.
| Fungal isolates | Clinical presentation | |||||||
|---|---|---|---|---|---|---|---|---|
| Tinea capitis | Tinea unguium | Tinea faciei | Tinea cruris | Tinea manuum | Tinea corporis | Tinea cruris | Total (%) | |
|
| 2 | 1 | 1 | 4 (14.2) | ||||
|
| 1 | 1 (3.5) | ||||||
|
| 1 | 1 | 1 | 1 | 2 | 6 (21.4) | ||
|
| 1 | 1 | 2 (7.1) | |||||
|
| 2 | 2 (7.1) | ||||||
|
| 1 | 1 | 2 (7.1) | |||||
|
| 1 | 1 (3.5) | ||||||
|
| 1 | 1 (3.5) | ||||||
|
| 1 | 1 (3.5) | ||||||
|
| 1 | 1 (3.5) | ||||||
|
| 4 | 1 | 5 (18.5) | |||||
|
| 1 | 1 (3.5) | ||||||
|
| 1 (3.7%) | 11 (40.7%) | 1 (3.7%) | 3 (11.1%) | 1 (3.7%) | 9 (33.3%) | 1 (3.7%) | 27 (100) |
Figure 7Hygienic status of positive cases.
Binary logistic regression analysis of risk factors associated with increased fungal infection.
| Risk factors associated with increased fungal infection. | Presence of risk factor among fungal positive cases (%) | Absence of risk factor among fungal positive cases (%) | Adjusted odds ratio |
|
|---|---|---|---|---|
| Sweating nature of skin | 23 (85.18) | 4 (14.81) | 10 | <0.001 |
| Poultry and cattle farm occupation | 8 (29.62) | 11 (40.74) | 3 | 0.08 |
| Knowledge on fungal infection | 9 (33.33) | 18 (66.66) | 1 | 0.7 |