Disseminated cryptococcosis caused by Cryptococcus neoformans a case report and review / 中国热带医学

@#Abstract: To analyze the clinical, therapeutic and laboratory characteristics of disseminated cryptococcosis caused by Cryptococcus neoformans invading the blood stream in patient with liver cirrhosis and splenectomy. A 30-year-old male underwent splenectomy plus pericardial devascularization due to "splenomegaly and hypersplenism" in March in 2016. The patient had intermittent fever after operation for many times, and successively accompanied with back pain, left lower limb abscess and right hip pain. The highest body temperature was 39 ℃. CT and MRI revealed the lung lesion and multiple bone destruction. During that period, the effect of antibiotics was not good. On April 19th, 2017, Gram's stain, India ink stain, API 32C, Vitek 2 Compact, ribosomal ITS and IGS sequence analysis were performed to identify the strain isolated from the pus and blood stream. The serum of the patient was detected for cryptococcal antigen. Antifungal susceptibility test was used to determine drug sensitivity and minimum inhibitory concentration (MIC). The Cryptococcus neoformans isolated from fresh pus specimen showed a prominent, thick capsule after India ink stain. The colonies isolated from pus and blood stream were identified Cryptococcus neoformans using API 32C, Vitek 2 Compact, and sequence analysis of rDNA ITS and IGS. Cryptococcal capsule antigen was positive. The minimal inhibitory concentrations of 5-Flucytosine, amphotericin B, fluconazole, itriconazole, voriconazole against the isolate were <4 μg/mL, <0.5 μg/mL, 4 μg/mL, ≤0.25 μg/mL, 0.125 μg/mL respectively. The patient was initially treated with intravenous amphotericin B and flucytosine. After anti-Cryptococcus treatment for two months, the patient clinically improved, and the lesions were reduced on a follow-up CT scan. The patient made a full functional recovery after treatment for six months. Cryptococcosis has hidden onset, atypical clinical symptoms and lack of specificity. Blood stream is the main channel for Cryptococcus to spread and involve many organs of the whole body, including skin, bone and so on. Therefore, early use of blood culture to monitor blood flow dissemination, actively removing the primary focus and cutting off the infection route in time and carrying out effective anti-Cryptococcus treatment are conducive to the patient's early recovery.

In vitro antifungal susceptibility of Candida speciesisolated from diabetic patients

Abstract INTRODUCTION This study aims to evaluate the antifungal susceptibility of different species of Candida isolated from diabetic patients against eight antifungal agents. METHODS Susceptibility testing of 111 clinical isolates of Candida species was performed against 8 antifungals using the M27-A3 protocol of the Clinical and Laboratory Standards Institute (CLSI). RESULTS Voriconazole, lanoconazole, and caspofungin showed the highest in vitro activity against all the isolates of C. albicans. Resistance against the tested antifungals was only observed in the C. albicans isolates. CONCLUSIONS Our finding revealed that resistance against amphotericin B, itraconazole, ketoconazole, posaconazole, and fluconazole can be observed in C. albicans.

Protothecosis in a patient with T cell lymphocytic leukemia / Prototecosis en un paciente con leucemia linfocítica de células T

Human protothecosis is a rare infection caused by algae of the genus Prototheca. Prototheca wickerhamii has been recognized as the main species that causes infection in immunocompromised hosts with deficits in innate or cellular immunity. We report a case of persisting subcutaneous protothecosis in a patient with T-cell large granular lymphocyte leukemia, who also presented a history of disseminated histoplasmosis.

La prototecosis humana es una infección rara causada por algas del género Prototheca. Prototheca wickerhamii ha sido reconocida como la principal especie causante de infección en huéspedes inmunocomprometidos, con déficit de inmunidad innata o celular. Presentamos un caso de prototecosis subcutánea persistente en un paciente con leucemia linfocítica granular de células T, con antecedentes de histoplasmosis diseminada.

Candidúria em adultos e crianças: prevalência e suscetibilidade a antifúngicos em pacientes ambulatoriais de Jataí-GO / Candiduria in adults and children: prevalence and antifungal susceptibility in outpatient of Jataí-GO

Introduction: The term candiduria refers to the presence of yeast in urine and Candida albicans is the most common agent. In general, routine laboratories do not perform identification and cultivation of yeast. Objectives: To determine the prevalence of Candida species and to evaluate the antifungal susceptibility of the species isolated in urine of outpatients Jataí-GO, between January-October 2013. Material and method: Urine samples containing fungal structures were plated out on Sabouraud agar with chloramphenicol. Differentiation was taken with the urease test, nitrogen and carbon sources assimilation, germ tube test, morphology on cornmeal agar and chromogenic agar cultivation. Susceptibility was evaluated at antifungal itraconazole, fluconazole, amphotericin B and ketoconazole. Results: 1,215 urine tests were performed, and 64 had fungal structures (5.3%). Two samples were lost, thus here we considered 62 isolates. From this total, 43 were identified as C. albicans (67.2 %), eight C. glabrata (12.5 %), five C. krusei (7.8%), three C. tropicalis (4.7%), and three could not determine the species (4.7%). Amphotericin B and ketoconazole inhibited 94.9% of the isolates. On the other hand, 55.9% and 54.2 % were resistant to itraconazole and fluconazole, respectively. The resistance rates of both fluconazole and itraconazole for C. glabrata and C. albicans, as fluconazole for C. albicans and C. krusei, showed significant differences (p < 0.05). Conclusion: These data demonstrate the importance of conducting a full identification and susceptibility to antifungal agents in samples with yeast infection...

Introdução: O termo candidúria designa a presença de leveduras na urina e Candida albicans é o agente mais comum. Em geral, os laboratórios de rotina não realizam o cultivo e a identificação da levedura. Objetivos: Determinar a prevalência de espécies de Candida e avaliar o perfil de sensibilidade aos antifúngicos das espécies isoladas em urina de pacientes ambulatoriais do município de Jataí-GO, entre janeiro e outubro de 2013. Material e método: Amostras de urina que continham estruturas fúngicas foram semeadas em ágar Sabouraud com cloranfenicol. A diferenciação foi feita com provas da urease, assimilação de fontes de nitrogênio e carbono, tubo germinativo, morfologia em ágar fubá e cultivo em ágar cromogênico. Foi avaliada a sensibilidade aos antifúngicos itraconazol, fluconazol, anfotericina B e cetoconazol. Resultados: Foram realizados 1.215 exames de urina, sendo que 64 apresentaram estruturas fúngicas (5,3%). Houve perda de duas amostras, assim, considerou-se 62 isolados. Desse total, 43 foram identificadas como C. albicans (67,2%); oito, C. glabrata (12,5%); cinco, C. krusei (7,8%); três, C. tropicalis (4,7%); e em três não foi possível determinar a espécie (4,7%). Anfotericina B e cetoconazol inibiram 94,9% dos isolados. Por outro lado, 55,9% e 54,2%, respectivamente, apresentaram resistência a itraconazol e fluconazol. As taxas de resistência a itraconazol e fluconazol de C. glabrata e C. albicans e também do fluconazol entre C. albicans e C. krusei apresentaram diferenças significativas (p < 0,05). Conclusão: Os dados demonstram a importância de se realizar a identificação completa e também o antifungigrama para amostras que apresentam infecção por leveduras...

Cellular characterisation of Candida tropicalis presenting fluconazole-related trailing growth

We assessed fluconazole susceptibility in 52 Candida tropicalis clinical strains using seven antifungal susceptibility methods, including broth microdilution (BMD) [standard M27 A3 (with neutral and acid pH), ATB Fungus 3, Vitek 2 system and flow cytometric analysis] and agar-based methods (disk diffusion and E-test). Trailing growth, detection of cell-associated secreted aspartic proteases (Saps) and morphological and ultrastructural traits of these clinical strains were also examined. The ranges of fluconazole 24 h-minimum inhibitory concentration (MIC) values were similar among all methods. The essential agreement among the methods used for MIC determinations was excellent and all methods categorised all strains as susceptible, except for one strain that showed a minor error. The presence of the trailing effect was assessed by six methods. Trailing positivity was observed for 86.5-100 percent of the strains. The exception was the BMD-Ac method where trailing growth was not observed. Morphological and ultrastructural alterations were detected in C. tropicalis trailing cells, including mitochondrial swelling and cell walls with irregular shapes. We tested the production of Saps in 13 C. tropicalis strains expressing trailing growth through flow cytometry. Our results showed that all of the C. tropicalis strains up-regulated surface Sap expression after 24 h or 48 h of exposure to fluconazole, which was not observed in untreated yeast strains. We concluded that C. tropicalis strains expressing trailing growth presented some particular features on both biological and ultrastructural levels.

The Optimal Wavelength of Spectrophotometric Broth Microdilution Antifungal Susceptibility Test for Flucytosine and Three Azoles / 대한진단검사의학회지

BACKGROUND: There is no guideline for the appropriate wavelength at which to measure the optical density (OD) value in broth microdilution antifungal susceptibility testing, although a spectrophotometric reading method is commonly used. The present study aimed to analyze the difference in the OD values over the range of visible light and to ascertain the optimal wavelength for the spectrophotometric method of microdilution testing. METHODS: We measured the OD of background blank controls of broth medium, antifungal agents, and inocula of five type strains using a Synergy HT multi-detection microplate reader at 5-nm intervals from 380 nm to 760 nm. We also estimated the OD differences between the 50% of growth control and blank control. RESULTS: The OD of the blank control showed a parabola shape with two peaks and steadily decreased at longer wavelengths. The curves of the antifungal agent were similar to those of blank controls, and the influence of each antifungal agent on the OD was minimal. For the difference in OD between 50% of growth control and the blank control, the curve was the opposite of the blank control, and the OD increased steadily at the wavelengths above 600 nm. CONCLUSIONS: The range between 600 nm and 700 nm was the optimal wavelength for broth microdilution antifungal susceptibility testing, although any wavelength within the visible light spectrum can be used.

Antifungal Susceptibility Testing of Dermatophytes / 대한의진균학회지

BACKGROUND: A standardized reference method for dermatophytes in vitro susceptibility testing is lacking. However, with increasing variety of drugs available to treat dermatophytosis, the need for a reference method for dermatophytes testing has become apparent. OBJECTIVE: To evaluate a method of quantifying dermatophytes, the standards for broth microdilution method and evaluation of the availability of disk diffusion method in antifungal susceptibility testing for dermatophytes. METHODS: 14 Candida species (sp.), 30 Trichophyton(T.) mentagrophytes, 9 T. raubitschekii and 11 T. rubrum were tested for fluconazole susceptibility by the broth microdilution method and disc diffusion method. Candida sp. was tested according to National Committee for Clinical Laboratory Standards (NCCLS) M27-A and M44-A. Broth microdilution method for T. mentagrophytes, T. raubitschekii and T. rubrum was operated according to NCCLS M38-A. Disk diffusion method for T. mentagrophytes, T. raubitschekii and T. rubrum was tested refer to NCCLS M44-A. RESULTS: The disk diffusion method showed 50% correlation rate with the broth microdilution method for antifungal susceptibility testing for Candida species. The MIC reading point and incubation time of the broth microdilution method for T. mentagrophytes, T. raubitschekii and T. rubrum are Spec-50 and from 7, 6 and 9 days. Relation between the broth microdilution method and disk diffusion method for dermatophytes is poor. CONCLUSIONS: The good method for quantifying dermatophytes is using vortexing only or liquid nitrogen and homogenizer. Standards of MIC reading point and incubation time of microdilution method for dermatophytes are Spec-50 and from 6 to 9 days. It appears that the disk diffusion method is not recommended method for the antifungal susceptibility testing of dermatophytes.

The Evaluation of Clinical Utility of ATB FUNGUS 2 for Antifungal Susceptibility Testing in Candida Species / 대한임상미생물학회지

BACKGROUND: Although the National Committee for Clinical Laboratory Standards (NCCLS) defined a standard reference broth microdilution method for testing the susceptibility of Candida species to antifungal drugs, many clinical laboratories require easier but reliable alternatives for routine antifungal susceptibility testing. We evaluated ATB FUNGUS 2 (bioMerieux, France.; ATB) compared to the method recommended by the NCCLS (NCCLS). METHODS: A total of 28 strains of Candida species consecutively isolated from blood and CSF cultures at Asan Medical Center from April to June 2004 were tested. In addition, 12 strains comprising C. krusei (3), C. glabrata (7) and C. guilliermondii (2) from the collection of Chonnam National University Hospital were included in the study. These strains were tested for minimum inhibitory concentrations (MICs) against flucytosine (FC), fluconazole (FZ), itraconazole (IZ) and amphotericin B (AB) by both of ATB and NCCLS. In NCCLS, MICs were read using a spectrophotometer after 24 and 48 hour-incubation. RESULTS: The concordance rates of MICs between ATB and NCCLS after 24 hour-incubation were 100%, 75%, 89% and 96% within two-fold dilution and 100%, 97%, 97%, 100% within four-fold dilution for FC, FZ, IZ and AB, respectively. For C. krusei, all three FC and FZ-resistant strains were either intermediate or SDD and one IZ-resistant strain was SDD in ATB, respectively. One C. tropicalis strain resulted in AB MICs of 0.5 microgram/mL in NCCLS, but 2 microgram/mL in ATB. CONCLUSIONS: ATB showed good concordance rates with NCCLS after 24 hour-incubation. ATB appears to be a useful alternatives to NCCLS for routine antifungal susceptibility tests. However, ATB needs further evaluation with more clinical strains, especially those resistant to antifungal agents.

In-Vitro Susceptibilities of Voriconazole Against Korean Clinical Aspergillus Isolates / 대한의진균학회지

BACKGROUND: Voriconazole is a potent new triazole antifungal agent expected to be particularly useful for the treatment of invasive aspergillosis. However, in vitro susceptibility of voriconazole for clinical strains of Aspergillus species isolated in Korea has not been fully surveyed. OBJECTIVE: We determined minimum inhibitory concentrations (MICs) of voriconazole for clinical Aspergillus isolates. METHODS: A total of 100 clinical isolates of Aspergillus species (40 A. fumigatus, 24 A. flavus, 17 A. niger, 17 A. terreus and 2 A. nidulans) was tested. In vitro voriconazole susceptibility testing was accomplished utilizing the National Committee for Clinical Laboratory Standards (NCCLS) broth microdilution method M38-A. MIC of voriconazole was determined using RPMI medium at 48 h of incubation. RESULTS: Among the 100 isolates of Aspergillus species tested, 98% were inhibited by or =2 microgram/mL were 0/40 (0%) in A. fumigatus, 1/24 (4%) in A. flavus, 1/17 (6%) in A. niger, 0/17 (0%) in A. terreus, and 0/2 (0%) in A. nidulans. CONCLUSION: These data demonstrate promising in-vitro activity of voriconazole against clinical strains of Aspergillus species isolated from Korean patients.