Sensitivity and specificity of potassium hydroxide and calcofluor white stain to differentiate between fungal and Pythium filaments in corneal scrapings from patients of Pythium keratitis

Purpose: To assess the sensitivity of potassium hydroxide and calcofluor white (KOH+CFW) mount in the diagnosis of Pythium keratitis and concordance among microbiologists. Methods: Three microbiologists evaluated the microscopic images of KOH + CFW mounts of confirmed cases of Pythium and fungal keratitis seen between January 2019 and February 2021. The filaments were compared using specific differentiating features. The sensitivity and specificity of KOH + CFW in diagnosing Pythium infection were evaluated along with concordance among the microbiologists. Results: Sixty consecutive cases with confirmed growth of fungus or Pythium insidiosum (n = 29) were evaluated. The sensitivity of KOH + CFW in the correct identification of Pythium filaments ranged from 79.3% to 96.5% among three microbiologists. There was good interobserver (k = 0.76–0.90) and intraobserver (k = 0.70–0.97) agreements among three microbiologists. The differentiating findings (P < 0.0001) suggestive of Pythium filaments were the absence of septae in 23 (79.3%) and collapsed walls in 22 (75.9%) cases. Conclusion: KOH + CFW has good sensitivity and specificity in the diagnosis of Pythium keratitis with good interobserver and intraobserver concordance.

Epidemiología de la Onicomicosis Pedis en adultos hospitalizados en un servicio de medicina en un hospital de tercer nivel en Chile / Epidemiology of Onychomycosis pedisinhospitalized adults at the internal medicine ward of a high complexity hospital in Chile

La prevalencia global de la onicomicosis pedis es de 4,3%, y en hospitalizados puede llegar hasta 8,9%. Aun así, se propone que está ampliamente subdiagnosticada. Personas añosas con comorbilidades presentan mayor riesgo de onicomicosis pedis y de sus complicaciones. Se examinaron aleatoriamente a 64 pacientes hospitalizados en el Servicio de Medicina del Hospital San José. A aquellos con signos clínicos de onicomicosis pedis se les realizó un examen micológico directo (MD) y estudio histopatológico de un corte de uña teñido con PAS (Bp/PAS). Muestra de 64 pacientes, un 78,1% presentó onicomicosis pedis clínica y en un 70,3% se confirmó el diagnóstico con MD y/o Bp/PAS positivo. De los pacientes con onicomicosis confirmada, el promedio de edad fue de 67,8 +/- 12,3 años. Un 44% correspondió al sexo femenino y un 56% al sexo masculino. La onicomicosis pedis en el servicio de medicina interna del Hospital San José es una condición frecuente. El conjunto de MD y Bp/PAS podría ser considerado como una buena alternativa diagnóstica. (AU)

Onychomycosis of the toenails has a global prevalence of 4,3% and can reach up to 8,9% in hospitalized patients. It has been hypothesized that it is widely under diagnosed. Aged patients with multiple diseases have an increased risk of Onychomycosis and its complications. 64 patients of the internal medicine ward were randomly selected. Those who had clinical signs of onychomycosis of the toenails were tested with direct microscopy and histological study of the nail plate with PAS staining. Of the 64 patients, 78,1% (50) had clinical signs of onychomycosis of the toenails and in 70,3% (45) the diagnosis was confirmed either by direct microscopy and/or by histological study of the nail plate with PAS staining. The mean age for the group with onychomycosis was 67,8 +/- 12,3 ages. 44% were female and 56% were male. Onychomycosis of the toenails is a frequent condition at the internal medicine ward of the San José Hospital. The direct microscopy together with the histological study of the nail plate with PAS staining seem to be a good diagnosis alternative. (AU)

Five percent potassium hydroxide for the treatment of anogenital warts: A systematic review and meta-analysis

@#<p><strong>BACKGROUND AND OBJECTIVES:</strong> Potassium hydroxide (KOH) is effective and safe as treatment of viral dermatoses. No systematic review has been done reporting its efficacy as a treatment for anogenital warts.</p><p><strong>METHODS:</strong> A systematic literature search for controlled clinical trials using KOH, any drug or ablative procedure measuring the clearance rate was conducted. Analysis was done using RevMan v5.3 software.</p><p><strong>RESULTS:</strong> Four low quality trials, composed of 197 patients were included but only two qualified for meta-analysis. Two studies compared KOH to cryotherapy while the two other trials compared KOH to intralesional 5-fluorouracil (FU) + salicylic acid (SA) and carbon dioxide (CO2) laser vaporization. The KOH group showed a higher clearance rate compared to cryotherapy (RR= 1.40, P> 0.05, I2=39 %) and no recurrence was noted (RR= 0.17, P> 0.05, I2=0) but the difference is not statistically significant. Isik et al., 2014 and Asadi et al., demonstrated that there was no significant difference among groups receiving KOH, 5-FU+SA and CO2 laser vaporization in the mean lesion count and size at follow up visits. (P > 0.05).</p><p><strong>CONCLUSIONS:</strong> Potassium hydroxide has comparable efficacy to the present treatment modalities but well-structured RCTs are needed to further support its use.</p>

Fluorescent staining with hypersensitivity and enhancement for early diagnosis of superficial fungal infection / 临床检验杂志

Objective To evaluate the application of novel fluorescent staining method with hypersensitivity and enhancement for microscopic examination of superficial fungal.Methods A total of 200 cases with clinically suspected superficial fungal infection were screened by the hypersensitive,enhanced fluorescent staining,calcofluor white staining and microscopic examination with 1.78 mol/L potassium hydroxide (KOH) based smear assay,respectively.The positive percentages of the different methods were calculated and compared.Results In the developed fluorescent staining examination,clean background was shown in the view field.The hyphae and spores displayed in bright blue,thus fungal morphology was so distinct that they were easy to be distinguished.Compared with calcofluor white staining and KOH based smear,the fluorescent staining showed high positive rate with significant difference respectively (x2 =17.984,P ＜ 0.05;x2 =32.063,P ＜ 0.05).Conclusion The novel fluorescent staining should be a rapid,accurate method for microscopic examination of fungi,which is worthy to be widely used in clinical laboratories for early diagnosis of fungal infection.

Comparing the Effectiveness of Sabouraud Dextrose Agar and Dermatophytes Test Medium for Isolation of Dermatophytes.

Background: Dermatophytes affects more than 30% of the population, usually as superficial mycosis but also present as deeper subcutaneous tissue infection in rare occasions. Because of ambiguous clinical presentations of dermatophytosis need to diagnose accurately to avoid mismanagement. The present study was selected to know the significance of KOH (Potassium Hydroxide) in diagnosis of dermatophytosis and to compare Sabouraud Dextrose Agar (SDA) with Dermatophytes Test Medium (DTM) in isolation of dermatophytes. Methods: A total of 124 patients were included in this study who was diagnosed as clinically suspected dermatophytosis at Department of DVL. Samples were collected and inoculated in to Sabouraud Dextrose Agar with Chloramphenicol and Cycloheximide, Dermatophytes Test Medium and also KOH mount was done. Results: Out of 124 clinically suspected dermatophytosis studied population, 78 (62.9%) were culture positive. Tinea corporis (29.4%) was affected predominantly followed by Tinea cruris (21.7%) and Tinea capitis (17.9%). On correlation of culture positivity with KOH microscopy, 15 patients (12.09%) were culture positive and KOH negative. 12 (9.6%) patients out of 124 were KOH positive and culture negative. The isolation rate in this study from SDA was 93.5% and that of DTM was 100%. On comparing of dermatophytes isolation from clinical samples among DTM and SDA, shown statistically insignificant (P>0.05). Conclusion: KOH gives rapid probable diagnosis to start empirical therapy, lesser sensitive than culture media. Both SDA and DTM gives good isolation results, where as DTM is superior than SDA in isolation and aid in easy interpretation.

Efficacy and safety of 1% terbinafine hydrochloride versus 2% sertaconazole cream in the treatment of tinea corporis.

Background: Tinea corporis is a common superficial dermatophytosis seen in tropical countries. This study was done to compare the efficacy and safety of topical antifungal agents, terbinafine versus sertaconazole in the treatment of tinea corporis. Methods: This study was conducted in Babuji Hospital and Chigateri Government Hospital, Davangere. A total of 60 (n=60) patients were included and divided into two groups of 30 patients each in the study. 1st group - received topical 1% terbinafine hydrochloride and 2nd group - received 2% sertaconazole cream. Patients were advised to apply cream twice daily for 4 weeks. Improvement in clinical parameters like erythema, scaling, itching, and potassium hydroxide (KOH) mount were taken for assessing the efficacy of drugs. They were followed-up at the end of 2, 4, and 6 weeks to assess the improvement of the condition. Complete cure rate was defined as mycological cure with a complete absence of clinical signs and symptoms. For safety data of both drugs presence of any local side effects (like stinging sensation, swelling and increased erythema) were analyzed in both groups. Statistical analysis was done using students paired t-test and unpaired t-test. Results: When two groups were compared at the end of 2 weeks, complete cure rate for terbinafine was 80% as compared to 63.3% for sertaconazole (p<0.003). However, at the end of 4 weeks, sertaconazole was as effective as terbinafine and statistically non-significant (p>0.05) results were obtained. KOH mount was negative in both groups at the end of 2nd week. Local side effects like erythema, swelling, stinging sensation were not noticed during the study in both the groups. Conclusion: From this study, it was shown that 2% sertaconazole cream was as effective as 1% terbinafine cream, though 1% terbinafine had higher rates of complete cure at the end of 2 weeks as compared to sertaconazole.

Standardization of Ethanol Potassium Hydroxide Volumetric Solution by Potentiometric Titration / 中国药师

Objective: To improve the standardization method for ethanol potassium hydroxide volumetric solution. Methods: A new potentiometric titration method was established and compared with the indicator method described in Chinese Pharmacopeia (2010 edition) . Results:There was no significant difference between the results of the potentiometric method and the indicator method( P>0. 05). Furthermore, the potentiometric titration had significant jump range, good precision and high reliability. Conclusion:The po-tentiometric method can be used in the standardization of ethanol potassium hydroxide volumetric solution.

Determination of Sulfurous Anhydride in Rhizoma Dioscoreae by Ion Chromatography-Direct Extraction / 中国药师

Objective:To establish a quantitative analysis method to determine the content of sulfurous anhydride in Rhizoma di-oscoreae by ion chromatography-direct extraction. Methods:Sulfurous anhydride was extracted by KOH solution (25 mmol·L-1). An IonPac? AS11-HC column(250 mm × 4 mm, 9. 0 μm) was used. The column temperature was 20℃, the eluent was KOH solution (20 mmol·L-1 ) at flow rate of 1. 00 ml·min-1 and the conductivity temperature was 20℃. Results:There was a good linear rela-tionship between the injection quantity (1.160-29.100 μg)and the peak area of sulfite(r =0.999 9). The average recovery was 98. 9%(RSD=0. 6%, n=9). The quantitation limit was 1. 38 ng·ml-1. Conclusion: The method is simple, accurate and rapid, which is appropriate for the quantitative analysis of sulfite anhydride in Rhizoma dioscoreae.

Treatment of Pityriasis Versicolor. A Comparative Study of Topical 4% Potassium Hydroxide Solution Versus 1% Clotrimazole Solution.

Aims: To evaluate the effectiveness of topical 4% potassium hydroxide (KOH) solution in the treatment of pityriasis versicolor in comparison with topical 1% clotrimazole solution. Study Design: Single-blinded, comparative therapeutic study. Place of the Study: Department of Dermatology and Venereology – Baghdad Teaching Hospital-Baghdad, between June 2008 and August 2009. Methodology: We included 90 patients divided into 2 groups: group A (4% KOH), Includes 46 patients and group B (1% clotrimazole), and includes forty four patients. Skin scraping test was done for all patients. KOH was applied once daily, while clotrimazole solution twice daily for 2 or 4 weeks according to the response. Results: Eighty patients completed the study; forty in each group. In group A, 31 (77.5%), 8(20%) and 1 (2.5%) patients showed complete, partial and no response respectively after 2 weeks. After 4 weeks, 39 (97.5%) patients showed complete response and 1 (2.5%) patients showed partial response. In group B, 20 (50%), 18 (45%) and 2 (5%) patients showed complete, partial response and no response respectively after 2 weeks. After 4 weeks, 38 (95%) patients showed complete response and 2 (5%) patients showed partial response. There was a significant difference at 2 weeks of treatment. Group A showing a better response than group B (p=0.02). Itching, burning sensation, and erythema were detected in few patients of both groups. Conclusion: Topical 4% potassium hydroxide solution seems to act more rapidly than 1% clotrimazole solution for pityriasis versicolor.

Fungal keratitis in and around visakhapatnam.

Introduction: Corneal infection of fungal etiology is very common and represents 30% to 40% of all cases of culture positive infectious keratitis. Hence an understanding of the epidemiological features is important in rapid recognition, timely institution of therapy, optimal management and prevention of this disease entity. Objectives: To isolate the specific fungal agents causing keratitis. To determine the risk factors and other epidemiological characteristics of infectious keratitis. To evaluate the importance of direct microscopy in the isolation of etiological agents and institution of therapy. Material Methods: Corneal scrapings were collected under strict aseptic conditions from each patient. The scrapings were subjected to direct microscopy using 10% Potassium Hydroxide (10% KOH), fungal culture and identification by standard microbiological techniques. Results & Conclusions: Fungal isolates were obtained in 30 out of 100 samples. The predominant fungal isolate was Fusarium spp. (30%), followed by Aspergillus spp. (26.66%). Corneal ulcers showed a higher prevalence in the later age groups (31-70 yr), representing a total of 89.99% of the fungal isolates. Male preponderance was seen, with 70% of the fungal ulcers occurring in males. 93.33% of the ulcers occurred among the lower socio economic group and 80% in the rural areas (villages). Agricultural labourers contributed to 63.33% of the corneal ulcers, and peak incidence of corneal ulceration was seen during the monsoon season- 43.33%. History of corneal trauma (83.33%), with vegetative matter (68%), was the most common predisposing factor noted. 10% KOH mount was positive in 28 out of 30 fungal ulcers- 93.33% sensitivity.

Quantitative determination of Asenapine in both bulk and formulations using neutralization titrations.

Asenapine is used in the treatment of schizophrenia disease.Asenapine mainly control the psychotic symptoms’ mainly antagonist to various receptors like, serotonin (5-HT1A, 5- HT1B,5-HT2A,5-HT2B,),histamine, and dopamine(D1,D2,D3,D4) receptors. It is also lower affinity towards muscaranic and acetylcholine receptors. In the present study, simple titrimetric method was developed. Respective quantities of Asenapine were taken in aqueous methanol titrated against 0.1N sodium hydroxide acid and 0.1N potassium hydroxide acid using phenolphthalein as an indicators for neutralization titration. This method were found to be sensitive and inexpensive, do not require any sample processing steps and can be utilized for estimation of asenapine in bulk and formulations.

Potassium Hydroxide (KOH) Wet Preparation for the Laboratory Diagnosis of Suppurative Corneal Ulcer.

Background: Suppurative keratitis is a common ophthalmic condition mostly caused by fungi. Apart from fungal culture, wet preparation using 10% Potassium hydroxide (KOH) for microscopic detection of fungal elements is a rapid and accurate method of laboratory diagnosis. Purpose: This prospective and cross sectional study was undertaken in order to evaluate the diagnostic sensitivity of wet preparation microscopy using KOH for detection of fungal agents from suppurative corneal ulcer patients. Methodology: Fifty six (56) consecutive clinically suspected patients of suppurative corneal ulcer attending Rajshahi Medical College Hospital (RMCH) during the period from July, 06 to June, 07 were included. Corneal swabs were taken aseptically for detection of bacteria in gram-stained smear and culture. Conventional mechanical corneal scrapings were collected under topical anesthesia and utilized for microscopic detection of fungal agents in KOH wet preparation and fungal cultures in the department of Microbiology of Rajshahi Medical College. Results: Culture yielded microbial growths in 47(83.93%) out of 56 samples of corneal ulcer that included 24 (42.86%) pure fungal growths, 14 (25.0%) pure bacterial growths and 09 (16.07%) mixed microbial growths (both bacteria and fungi). Direct microscopical examination using 10% KOH wet preparation detected 28 fungal agents out of total 33 fungal cases (combining both pure and mixed fungal growths in culture). Diagnostic sensitivity of wet preparation microscopy was found to be 84.85% by comparing its performance to fungal culture yields, which is the ‘gold standard’ for laboratory diagnosis. Conclusion: This limited study has revealed that wet preparation can be a tentative diagnosis of fungal keratitis and can be accurately relied upon for initiating prompt anti-fungal therapy and also recommended as a cost-effective method for laboratory diagnosis especially where culture facility is not available.

An Open, Randomized, Comparative Clinical and Histological Study of Imiquimod 5% Cream Versus 10% Potassium Hydroxide Solution in the Treatment of Molluscum Contagiosum

BACKGROUND: Although molluscum contagiosum (MC) resolves spontaneously, there are several reasons to treat this dermatological disorder. OBJECTIVE: To evaluate the safety and efficacy of 5% imiquimod cream versus 10% potassium hydroxide (KOH) solution in treating MC, and to propose the mechanism of cure by observing the histological findings. METHODS: Imiquimod or KOH were applied by the patient or a parent 3 days per week until all lesions cleared. The number of MC lesions was counted and side effects were evaluated at 5 points during the treatment (the initial visit, week 2, week 4, week 8, and week 12). Histological changes were compared between 2 patients of each group, before and after the 2 weeks of application. RESULTS: In both group, the mean lesion counts decreased all through to week 12, and the reduction in number of lesions were statistically significant in both groups (p <0.005). Over 40% of each group developed local side effects, and no systemic side effects were noted in either group. Before treatment, histological findings showed little or no dermal infiltrates. After treatment, specimens showed dense lymphocytic infiltrates, especially T cells, around the lesions which had resolved. CONCLUSION: Both 10% KOH solution and 5% imiquimod cream are effective and safe treatment of MC.

Cutaneous zygomycosis: A possible postoperative complication in immunocompetent individuals.

Fungi in the class of zygomycetes usually produce serious infections in diabetics and immunocompromised hosts. Cutaneous zygomycosis is a less common form, with an unpredictable extent of anatomical involvement and clinical course. Here, we report two cases of primary cutaneous zygomycosis as postoperative complications in otherwise healthy females. Zygomycosis was suspected and specimens from the surgical debridement were examined by microbiological and histopathological studies for confirming the clinical diagnosis. Rapid diagnosis, liposomal amphotericin B, and proper debridement of affected tissue are necessary to avoid a fatal outcome.

Predictive values of 10% potassium hydroxide examination for superficial fungal infection of the skin

Introduction Ten percent potassium hydroxide examination is one of the most frequently performed tests in dermatology. It is usually supplemented by fungal culture for detection of superficial fungal infection of the skin and its appendages. We aim to determine the predictive values of 10% potassium hydroxide examination in Sarawak General Hospital. Materials and Methods A retrospective review of 292 skin scraping results for 10% potassium hydroxide examination and culture was done between October 2003 and December 2004. Data for all the scrapings were analysed for predictive values, specificity, sensitivity and likelihood ratio with fungal culture as the gold standard investigation. Separate data analysis was done for those with onychomycosis. Results Positive cultures were noted in 80.8% of skin scrapping cases and 85.4% of onychomycosis cases. For the skin scrapping cases, the positive predictive value of 10% potassium hydroxide examination was 67.4%, negative predictive value of 16.9%, sensitivity of 12.3% and specificity of 75%. For those with onychomycosis, the positive predictive value was 75%, negative predictive value 13.6%, specificity 85.7% and sensitivity was 7.3%. The positive likelihood ratio for all cases and onychomycosis cases was 0.5 whereas the negative likelihood ratio was 0.9. Conclusion Ten percent potassium hydroxide examination has a very low negative predictive value and sensitivity, making it a poor investigative tool in Sarawak General Hospital. Thus, culture of the skin scraping for suspected superficial fungal infection of the skin and its appendages is of utmost importance. Steps to improve the quality of 10% potassium hydroxide examination are important as it is an easy and inexpensive test.