Myrtha Arango

Mucormycosis (Zygomycosis) in a Heart-Kidney Transplant Recipient: Recovery after Posaconazole Therapy

We describe the case of a diabetic patient who developed a severe invasive fungal infection due to Rhizopus species postoperatively after a dual heart/kidney transplantation with subsequent intensive immunosuppressive therapy. No improvement was noted with amphotericin B (deoxycholate) therapy, but salvage treatment with the new azole antifungal posaconazole (200 mg orally 4 times daily) resulted in dramatic clinical improvement as early as 1 week after the initiation of therapy that continued through 23 weeks of treatment, with marked clinical, mycological, and radiological improvements and no adverse events.

Treatment of Chromoblastomycosis with Itraconazole

The results of long-term itraconazole therapy in 10 patients with active chromoblastomycosis due to F. pedrosoi were reported. Therapy consisted of 100 or 200 mg/day of itraconazole, the length of therapy depending on the patients response (12 to 24 months). This new triazole proved effective in reducing the number, size, and severity of the lesions in nine of the patients. Those patients with minor involvement profited more from therapy and were cured; patients with moderate involvement achieved either minor or major improvement. In most cases, signs and symptoms began to improve after 6 months of therapy. Mycological tests (in which tissue samples were treated with potassium hydroxide and cultured) became negative in six patients, but the fungus was eradicated in only three patients. Itraconazole produced no side effects. In spite of the need for long-term therapy, this new azole derivative effectively controls the disease.

Residual pulmonary abnormalities in adult patients with chronic paracoccidioidomycosis: prolonged follow-up after itraconazole therapy.

Itraconazole effectively controls active paracoccidioidomycosis but appears not to hinder lung fibrosis. Clinical records and chest radiographs from 47 itraconazole-treated patients with prolonged posttherapy follow-up (mean follow-up period, 5.6 years) were analyzed; the radiographs were interpreted following pneumoconiosis standards that consider the lungs as 6 fields and grade damage according to the number of fields involved. Infiltrative lesions were observed at diagnosis in 93.6% of the patients. Fibrosis was observed in 31.8% of the patients at diagnosis and had not cleared at the end of the observation period in any of these patients. Fibrosis also developed de novo in 11 patients (25%), so that by the end of the follow-up period it was seen in 53.2% of patients overall. Fibrosis correlated with severity of infiltrates at diagnosis: fibrosis was present in 83% of patients with very severe infiltration and in 12.5% of patients with minor infiltration. Among patients with severe infiltration, fibrosis was present in 30%; this increased (to 75%) when bullae were concomitantly present at diagnosis. Prompt initiation of treatment is necessary to avoid the development of fibrosis.

Characteristics of the conidia produced by the mycelial form of Paracoccidioides brasiliensis

The sporulation capacities of the mycelial form of Paracoccidioides brasiliensis were determined. Five different culture media were used and four human isolates studied. Conidia were produced in three agar media, namely water-agar, glucose-salts and yeast-extract. Corn meal and Sabouraud dextrose agars failed to induce sporulation. Various types of spores were characterized with peculiar bulging arthroconidia and single-celled, pear-shaped conidia predominating. The size of these conidia varied from 3.6 to 4.6 micron in length. It is concluded that the mycelial form of P. brasiliensis produces characteristic spores if the proper culture media are employed.

The naked-tailed armadillo Cabassous centralis (Miller 1899): a new host to Paracoccidioides brasiliensis. Molecular identification of the isolate

The natural habitat of Paracoccidioides brasiliensis remains undefined but the repeated demonstration of infection by this fungus in the nine-banded armadillo Dasypus novemcinctus has opened interesting research avenues. We report here the isolation of this fungus from the spleen of a naked-tailed armadillo Cabassous centralis (Miller 1899) captured in a coffee farm localized in the Colombian endemic area for paracoccidioidomycosis. This particular isolate was identified by its dimorphism and also by comparison of the PbGP43 gene and ribosomal internal transcribed spacer regions (ITS) with recognized P brasiliensis strains. This finding extends the range of naturally acquired infections in mammals of the family Dasypodidae and confirms the existence of this human pathogen in areas where human paracoccidioidomycosis is known to occur.

Disseminated histoplasmosis in children: the role of itraconazole therapy.

OBJECTIVES To describe the clinical characteristics and laboratory diagnosis of seven children with disseminated histoplasmosis and evaluate the effectiveness of itraconazole therapy in this severe form of the mycosis as well as to determine the long term results of such treatment. METHODS The diagnosis of histoplasmosis was based on the direct observation of Histoplasma capsulatum var. capsulatum and/or on the isolation of the fungus from pathologic materials; the results of the serologic tests were taken into consideration. Chest roentgenograms also contributed to the diagnosis. PATIENTS The patients were seven rural children, five girls and two boys, ages 1 to 14 years (mean, 4.6), with a confirmed diagnosis of disseminated histoplasmosis and who had no underlying disease other than malnourishment. RESULTS The seven children experienced a subacute febrile syndrome for 4 months accompanied by anorexia, weight loss and signs of reticuloendothelial involvement such as lymph node hypertrophy, hepatomegaly and/or splenomegaly. The lung revealed roentgenographic alterations consisting mainly of nodular infiltrates. All patients received itraconazole orally in a mean dosage of 7.2 mg/kg/day, for variable periods (3 to 12 months), depending on the individual response and the toxic effects of the medication. One of the patients who was improving after 1 month of treatment was taken from the hospital by his guardian against medical advice and died shortly afterward. The remaining six patients responded to the treatment with marked clinical improvement and showed negative cultures and decreases in anti-H. capsulatum antibody titers after 3 months of treatment. Only one patient, the youngest and most severely affected child, exhibited hepatotoxicity, which subsided when itraconazole was discontinued. Extended follow-up studies revealed no relapses. CONCLUSION The results of this study indicate that itraconazole is effective for treatment of disseminated childhood histoplasmosis. More studies should be performed to determine the most appropriate dosage and the optimal duration of itraconazole treatment in children.

In vitro susceptibility testing of Paracoccidioides brasiliensis to sulfonamides.

A total of 60 clinical isolates of Paracoccidioides brasiliensis were tested for susceptibility to sulfadiazine and sulfadimethoxyne by the agar dilution technique. A modification of the Mueller-Hinton medium was devised which gave good growth of the yeast form. The minimum inhibitory concentrations for only 51.6% of the isolates were in the range of the recommended blood serum concentration (50 micrograms/ml). For 6 to 8% of the isolates, the minimum inhibitory concentrations were above 200 micrograms of both sulfadiazine and sulfadimethoxyne per ml. A significant decreases in susceptibility was demonstrated for one isolate obtained from a patient relapsing during sulfonamide therapy. Images

The isolation of Botryodiplodia theobromae from a nail lesion

Botryodiplodia theobromae not known to produce onychomycosis was repeatedly recovered from a healthy woman with evident lesions in a toe nail. Mycelial fragments were observed in the scales and the fungus was isolated in cycloheximide-free culture media. The report indicates that many fungi, hitherto considered non-pathogens, may still be able to colonize a vaiety of human tissues.

Histoplasmosis: results of the Colombian National Survey, 1992-2008

INTRODUCTION Histoplasmosis, a fungal disorder characterized by a wide spectrum of manifestations that range from subclinical infections to disseminated processes, affects both immunocompetent and immunosuppressed individuals. Histoplasmosis is not a reportable disease in Colombia and consequently, a survey was designed to collect histoplasmosis cases diagnosed in the country. OBJECTIVE The aim of this work was to analyze the data collected from 1992 to 2008. Materials and methods. The survey included demographic data, risk factors, clinical manifestations, imaging data, diagnostic methods and antifungal treatment. Patients were grouped according to risk factors and comparisons of the various findings were done. RESULTS A total of 434 surveys were gathered from 20 of the countrys Departments. Most patients (96.1%) were adults, 77% were males with a mean age of 38.4 years. Only 3.9% were children less than 15 years of age. In the adult population, AIDS was reported in 70.5% of the cases; additionally, in 7.0% patients other immunosuppressive conditions were informed. The most frequent clinical manifestations were fever (76.1%), cough (54.8%) and constitutional symptoms (56.8%). X rays abnormalities were represented mainly by infiltrates (65.9%) and nodules (17.1%). Diagnosis was made by microscopic observation of H. capsulatum in 49.6% patients, by culture in 58.0% and by serological test in 14.6% cases. Antifungal use was recorded in 52.5% cases. CONCLUSIONS Histoplasmosis is frequent in Colombia, especially in certain risk factor groups such as the HIV-infected population. Data collected from this large number of cases has allowed valid comparisons on various aspects of histoplasmosis in Colombia.

Presence and expression of the mating type locus in Paracoccidioides brasiliensis isolates.

Paracoccidioides brasiliensis has been classified in the phylum Ascomycota, order Onygenales, family Ajellomycetaceae, even in the absence of a known sexual cycle or mating system. The objective of this work was to determine the presence of the mating type locus in 71 P. brasiliensis isolates from various sources. A PCR assay using specific primers for the MAT 1 gene was developed and applied for the detection of such genes. Two heterothallic groups (MAT1-1 or MAT1-2) were recognized and, in some isolates, gene expression was confirmed indicating the existence of a basal gene expression. The distribution of two mating type loci in the studied population suggested that sexual reproduction might occur in P. brasiliensis. This finding points towards the possibility of applying a more precise definition of the concept of biological species to P. brasiliensis. Further studies should be conducted to confirm the sexual capacity of this fungus and its implications among phylogenetic species and geographical distribution.