S.A. Gumaa

Ketoconazole in the treatment of eumycetoma due to Madurella mycetomii

Eumycetoma is, at present, treated only by surgery which is amputation at times and mutilating excision at others. Surgical treatment is often followed by local, or rarely distant recurrence to regional lymph nodes and surrounding tissue. The results of the clinical trial with ketoconazole reported in this paper show that five of 13 patients were completely cured and four improved. It is worth noting that the daily dose for those cured was 400 or 300 mg while those who improved were on only 200 mg/day.

The host tissue reaction to Madurella mycetomatis: new classification

In this prospective study, three types of tissue reaction to mycetoma grains are described. Type I reaction is characterized by the adherence of neutrophils to the surface of the grain leading to its disintegration. In Type II reaction, the fragmented grain and the dead neutrophils are cleared by macrophages and multinucleated giant cells, while in Type III reaction there is a discrete well developed epithelioid granuloma with Langhanss giant cells. The three types of reaction are usually seen in different combinations in the same lesion.

Counterimmunoelectrophoresis in the diagnosis of mycetoma and its sensitivity as compared to immunodiffusion

Counterimmunoelectrophoresis used for the diagnosis of mycetoma was found superior to immunodiffusion (ID) especially when using neat serum and 1:2 dilution (P=less than 0.0001 with neat serum; and less than 0.01 with 1:2 dilution). It is recommended for routine use in mycology laboratories for following up patients on treatment and for confirming the diagnosis of sera that are weakly positive by ID.

Post-operative responses of paranasal Aspergillus granuloma to itraconazole

Paranasal Aspergillus granuloma is an invasive infection, seen mainly in tropical countries, involving the paranasal sinuses, orbit and brain. Previously surgical excision has been followed by a high relapse rate, 80% in some series, and mortality. This study involved the use of post-operative therapy with oral itraconazole in doses of 200-300 mg daily. Twenty-two patients were treated for a mean period of 19.7 weeks. Of 19 patients for whom follow-up data were available, 12 (62%) were rated as being in complete remission in a mean period of 17.2 months after the end of therapy. Only one patient developed progressive disease during itraconazole therapy. No serious adverse effect was seen. Use of itraconazole shows promise as a means of preventing relapse after surgery in this progressive infection.

Ultrastructural and immunogenic changes in the formation of mycetoma grains.

The differences in the fine structure and antigenic determinants of mycetoma fungi in the mycelial phase in vitro and in grains in vivo facilitate an interpretation of grain formation. Aggregates of hyphal elements with multiple and thickened walls was a feature of the fungi in vivo. Associated with hyphal wall material, numerous polysaccharide microfibrils were detected in grains of Madurella mycetomatis. These were not seen associated with hyphal elements in vitro and it is suggested that these structures may be concerned with the aggregation of fungal elements in the formation of grains. Antibodies directed against the fungi in vitro were shown, by indirect immunogold labelling, to bind at identical sites in fungal material grown in vitro as in mycetoma grains. However the grain matrix was not labelled, suggesting that part of the structure formed in vivo is composed of modified antigen or is host derived.

In vitro studies of antibiotic sensitivities of Streptomyces somaliensis ― a cause of human actinomycetoma

Ten Streptomyces somaliensis strains isolated from mycetoma patients were tested in vitro against 13 antibacterial agents. Rifampicin was the most effective antibiotic in terms of low minimum inhibitory concentration (MIC) followed by erythromycin, tobramycin, fusidic acid and streptomycin sulphate. The S. somaliensis strains were all resistant to trimethoprim, even though the combination of sulphamethoxazole and trimethoprim is commonly used as treatment.

Abdominal wall Mycetoma: an Unusual Presentation

Abstract Three cases of abdominal wall mycetoma in Sudan, caused by Streptomyces somaliensis, presenting as renal and retroperitoneal masses and a desmoid tumour, respectively, are reported.

A preliminary study on the ultrastructure of Actinomadura pelletieri and its host tissue reaction

This is the first report on the fine structure of Actinomadura pelletieri. The in vitro ultrastructure of the organism and that of the grain in vivo were similar. The grain consisted of packed filaments with a faintly electron-dense matrix in between. The individual filament was septate, the cytoplasm was either vacuolated or contained intracellular organelles and the cytoplasmic membrane was adherent to the filamentous wall, which has three electron-dense and two electron-lucent layers. The absence of cement substance around the grain may partially explain the aggressive and destructive behaviour of this organism and may probably also explain its good response to medical treatment. The inflammatory host reaction was similar to that seen with all mycetoma organisms except that there was a massive neutrophil reaction. This was confirmed by electron microscopy.

Mycetomas in goats

Naturally occurring mycetomas were found in 3 goats. Two had mycetomas on their hind legs and the third on its left scapula. In 2 goats the causative agents were identified by culture, histopathology and serology as Actinomadura madurae. In the remaining goat diagnosis was based only on histopathology and the causative agent was considered to be A. pelletierii. Despite minor differences between goat and human strains of A. madurae, it would seem that goats could be useful experimental models.

A case of African histoplasmosis from Sudan.

The first authentic case of African histoplasmosis from the Sudan is reported. The patient came from Dindir, along the southern part of the Blue Nile River. He had cutaneous and visceral leishmaniasis as well as the cutaneous form of African histoplasmosis. The latter was proved by culture and histopathology to be due to Histoplasma duboisii. The fungus was confined to the skin. H. duboisii may be more prevalent, and further studies in Dindir area are needed.