[Subcutaneous mycosis due to Scopulariopsis brevicaulis in an immunocompromised patient]

BACKGROUND

Scopulariopsis brevicaulis is a causal agent of onchomycosis. We report the unusual clinical manifestations caused by this opportunist fungus.

CASE REPORT

A 61-year-old man consulted in February 1997 for a budding lesion located on the right medial malleolus. This patient had had a liver transplantation for primary biliary cirrhosis in 1990 and had been taking prednisone and cyclosporine since this time. Cyclosporine had been recently replaced by tacrolimus. The histology examination of a lesion specimen taken from the ankle evidenced a dermal mycosis due to opportunist filamentous fungus. Total excision was performed. The patient then developed nodular lesions of the left elbow during the summer of 1997. Mycology culture of a skin biopsy grew numerous colonies of Scopulariopsis brevicaulis. Excision of the elbow lesion was delayed due to hospitalization for suspected graft rejection and development of insulin-dependent diabetes. The elbow lesion was then resected followed by a skin graft. The mycology examination identified the same causal agent.

DISCUSSION

This liver transplant recipient developed two unusual extra-ungual localizations (ankle and elbow) of a Scopulariopsis brevicaulis infection. Chronic immunosuppression favored development of the infection with a pseudo-epithéliomatous presentation. The histology and mycology examinations were necessary for positive diagnosis.

Diagnosis of malaria in non-endemic countries by the ParaSight-F test

QBC, examination of thin blood smears, and Parasight-F were performed for every case of malaria suspected between May 1997 and December 1998. Data from 310 patients were reported. Fifty had malaria infection diagnosed by QBC and thin blood film, among whom 39 had Plasmodium falciparum infection. Three of these 39 were negative with the Parasight-F test. Eleven patients had a positive ParaSight-F test but microscopic diagnosis methods were negative. Interpretation of these 11 positive ParaSight-F results is proposed to depend on clinical criteria.

Recurrent subcutaneous infection due to Scopulariopsis brevicaulis in a liver transplant recipient

We describe a case of recurrent Scopulariopsis brevicaulis subcutaneous infection, which occurred 6 years after the patient underwent liver transplantation. Combined surgery and long-term oral therapy with terbinafine resulted in a favorable outcome, although this is not the rule in the previously reported S. brevicaulis infections in immunocompromised patients.

[Diagnosis of malaria in non-endemic countries : value, limitations and complementarity of existing methods]

The biological diagnosis of malaria is urgent to avoid rapid and fatal outcome. Every year in France, 5,000 imported malaria cases are observed. Thin stained blood smear microscopical examination remains the reference method of diagnosis; however its performance is linked to the professional competence of the biologists. Thus easier methods have been developed (QBC test). Some of them, limited to the diagnosis of malaria due to Plasmodium falciparum do not require highly skilled personal to perform or interpret (antigen detection on dipsticks, tests Parasight or cardboard, ICT Malaria Pf), but limitations and errors occurred. These different tests must be complementary methods of traditional diagnosis. In association with microscopical examinations, they provide rapid and efficient diagnosis of malaria in non-endemic areas. Relying on our experience, the best association is: QBC + thin blood smear and depending of results antigen detection (ParaSight F, ICT Malaria Pf).

Asymmetric synthesis of 2-methyl cyclohexane carboxylic acids by heterogeneous catalysis: mechanistic aspects

The catalytic hydrogenation of (S)-alkyl-N-(2-methylbenzoyl)pyroglutamates was studied over supported rhodium and ruthenium catalysts at room temperature and a pressure of 5 MPa. The reaction was diastereoselective with the predominant formation of (1S,2R)-2-methylcyclohexane carboxylic acid with a diastereomeric excess (de) of up to 96%. The most stable conformation was determined by means of a combination of modelling calculations, NMR spectroscopy and X-ray structural determination. In this conformation, the carbonyl group of the pyroglutamate auxiliary shields one face of the aromatic ring. The observed selectivity may thus be explained by a preferential adsorption at the unshielded face which avoids steric repulsion by the C=O group to result in a cis hydrogenation. The addition of an amine, the nature of the support (alumina or active carbon) or of the metal (Rh or Ru) were shown to give additional stabilisation of the adsorption at the unshielded face to increase the diastereoisomeric excess.

Aspergillus Fumigatus antigen detection in sera from patients at risk for invasive aspergillosis

We have developed an inhibition enzyme immunoassay (inhibition-EIA) to monitor for the occurrence of invasive aspergillosis (IA) in sera from 45 immunocompromised (IC) patients. The test uses rabbit polyclonal antibodies and a mixture of components from Aspergillus fumigatus, containing three predominant antigens with molecular weights of 18,000, 33,000, and 56,000. Circulating antigens were found in five of seven proven cases of IA due to A. fumigatus. In two of the five positive cases, antigenemia was detected with inhibition-EIA earlier than with X ray or other biological methods. No antigens were detected in the sera from two patients with proven IA due to Aspergillus flavus and Aspergillus terreus nor in the sera from four patients with probable IA. Circulating antigens were not detected in the control group, composed of 30 healthy adult blood donors. Four of the 32 at-risk patients examined, though they displayed no definite evidence of IA, gave a positive result in this test. The sensitivity, specificity, and positive predictive value of inhibition-EIA were 71.4, 94.4, and 71.2%, respectively. The data were compared with those obtained by a latex agglutination assay of galactomannan (GM) that was positive in only one patient with probable IA. The higher sensitivity obtained by inhibition-EIA may well be due to its ability to detect circulating antigens other than GM in the sera of IC patients with IA. Detecting these antigens may improve the diagnosis of IA, as they may serve as markers of this infection.

Identification of amylase crystalloids in cystic lesions of the parotid gland

OBJECTIVE

To identify alpha-amylase crystalloid formations in parotid specimens obtained by fine needle aspiration.

STUDY DESIGN

The study concerned three cases of sialadenitis with crystalloid formation observed between 1993 and 1998. In one of these cases, transmission electron microscopy, mass spectrometry and measurement of amylase activity were used to characterize the nature of the crystalloids.

RESULTS

Light microscopy revealed the same crystalloid structure in all three cases. In one case, where the material was saved, a biochemical method made it possible to reveal high amylase activity, while protein electrophoresis and mass spectrometry were used to identify salivary alpha-amylase.

CONCLUSION

Crystalloids of salivary alpha-amylase can be identified by May-Grünwald-Giemsa and Papanicolaou stain and can be rapidly confirmed through determination of amylase activity.

[Fungal and parasitic nosocomial infections: importance and limitations of disinfection methods]

Due to the increase of opportunistic mycosis and parasitosis for several years, the management of fungal and parasitic risk in hospital has become a necessity and an obligation. The authors remind the main rules and knowledges essential to an optimal management of the fungal and parasitic disinfection in hospital. They summarize the efficiency of different disinfection processes in relation to yeasts, filamentous fungi, Pneumocystis carinii, Cryptosporidia and Microsporidia involved in hospital pathology.

Does hydrocortisone modify the in vitro susceptibility of Aspergillus fumigatus to itraconazole and amphotericin B?

To analyse if hydrocortisone could modify the in vitro susceptibility of Aspergillus fumigatus to antifungal drugs, we developed a procedure to test the susceptibility of an A. fumigatus strain to amphotericin B and itraconazole, grown in the presence and in the absence of hydrocortisone. Conidia were germinated in the presence or the absence of hydrocortisone in Czapek medium without antifungal drug. A dilution of these cultures (5x10(3) conidia ml(-1)) was spread onto Czapek-agarose plates containing both antifungal drug and hydrocortisone. The cfu per plate were enumerated and compared. A therapeutic concentration of hydrocortisone induced a significant increase in the susceptibility to itraconazole. Conversely, the susceptibility to amphotericin B was not significantly modified when this antifungal drug was associated with hydrocortisone.

Specific antibody detection in invasive aspergillosis by analytical isoelectrofocusing and immunoblotting methods

Aspergillus fumigatus antigens have been tested to determine their potential as aids in the diagnosis of invasive aspergillosis (IA). Immunoglobulin G (IgG) antibodies to these antigens were detected by analytical isoelectrofocusing in conjunction with immunoblotting. A total of 12 antigenic fractions, including culture filtrates and surface and mycelial extracts of A. fumigatus, were investigated. Eleven were reactive with serum specimens from patients with aspergilloma, which served as positive controls for the evaluation of a specific IgG response. Eight of 12 antigens showed good responses with serum specimens from patients with allergic bronchopulmonary aspergillosis, which were used to assess the sensitivity of IgG detection. No measurable reactivity was detected in 18 negative control serum specimens, while 11 of 13 patients with proven, highly probable, or probable cases of IA had anti-Aspergillus IgG to multiple antigenic preparations. Patients with IA who were capable of mounting a substantial humoral response to Aspergillus antigens gave an antibody profile with five antigenic preparations which seemed to be characteristic of the disease. Data show that this method is highly sensitive and may allow the selection of fractions which are both highly antigenic and specific for the detection of antibodies to Aspergillus antigens. They also indicate that the use of a spectrum of antigenic molecules is advisable, given the variability observed in the immune responses of individual patients.

Itraconazole in the treatment of aspergillosis: a study of 16 cases

Itraconazole, a new triazole antifungal agent, has marked in vitro activity against filamentous fungi, particularly Aspergillus. We studied three groups of patients suffering from aspergillosis (16 cases): six affected with aspergilloma, three with allergic bronchopulmonary aspergillosis and seven with invasive aspergillosis. The survey consisted in clinical, radiological, mycological and serological evaluations with respect to drug plasma levels. Itraconazole was given at a dosage of 200-400 mg day-1 for periods ranging from 14 to 488 days. Out of the 16 patients, nine responded to therapy (recovery or improvement) and one failed to respond. Three patients improved but experienced relapses and three others could not be evaluated because of liver function disorders, so that treatment had to be stopped prematurely.

Western blot detection of IgG anti-Aspergillus fumigatus elastase in sera of patients with aspergillosis

Anti-Aspergillus fumigatus alkaline protease IgG was investigated by Western blot. Specific IgG antibodies were detected in sera of two of nine patients with proven or highly probable invasive aspergillosis and in sera of one of eight patients with proven or highly probable allergic bronchopulmonary aspergillosis. No response was obtained in sera of 23 control patients. The specific but transient IgG response to this induced enzyme does not recommend its use as sole serodiagnostic aid.

Fungal polysaccharides

Fungal polysaccharides are cell wall components which may act as antigens or as structural substrates. As antigens, the role of mannans in Saccharomyces cerevisiae and Candida albicans, and of glycoproteins in Aspergillus fumigatus are discussed. Analyses on beta-glucan synthetase in Paracoccidioides brasiliensis and the inhibitory effect of Hansenula mrakii killer toxin on beta-glucan biosynthesis are also considered.