The data on visceral mycoses that had been reported in theAnnual of the Pathological Autopsy Cases in Japan from 1969 to 1994 by the Japanese Society of Pathology were analyzed epidemiologically. The frequency of visceral mycoses among the annual total number of pathological autopsy cases increased noticeably from 1.60% in 1969 to a peak of 4.66% in 1990. Among them, the incidences of candidiasis and aspergillosis increased the most. After 1990, however, the frequency of visceral mycoses decreased gradually. Until 1989, the predominant causative agent was Candida, followed in order by Aspergillus and Cryptococcus. Although the rate of candidiasis decreased by degrees from 1990, the rate of aspergillosis increased up to and then surpassed that of candidiasis in 1991. Leukemia was the major disease underlying the visceral mycoses, followed by solid cancers and other blood and hematopoietic system diseases. Severe mycotic infection has increased over the reported 25-year period, from 6.6% of the total visceral mycosis cases in 1969 to 71% in 1994. The reasons for this decrease of candidiasis combined with an increase of aspergillosis or of severe mycotic infection might be that (i) nonsevere (not disseminated) infections were excluded from the case totals, since they have become controllable by antifungal drugs such as fluconazole, but (ii) the available antifungal drugs were not efficacious against severe infections such as pulmonary aspergillosis, and (iii) the number of patients living longer in an immunocompromised state had increased because of developments in chemotherapy and progress in medical care.

Clinical isolates of Trichosporon cutaneum, the causative agent of trichosporonosis, were identified on the basis of DNA relatedness. Of the 10 strains from deep-seated and mucosa-associated infections, 9 were identified as T. asahii and 1 was identified as T. ovoides. The two superficial strains were identified as T. cutaneum and a variety of T. montevideense. These findings suggest that T. cutaneum is a heterogeneous species in clinical samples and that the causative agents of trichosporonosis exist in four or more species.

To study the relationship between the changes in visceral mycoses rates and recently advanced medical care in hematological settings, data on visceral mycosis cases with leukemia and myelodysplastic syndrome (MDS) that had been reported in the Annual of the Pathological Autopsy Cases in Japan in 1989, 1993 and 1997 were analyzed. The frequency rate of visceral mycoses with leukemia and MDS was 27.9% (435/1557) in 1989, 23.0% (319/1388) in 1993 and 22.3% (246/1105) in 1997. In comparing the rate of mycoses in recipients of organ or bone marrow transplantation with that of non-recipients, that of recipients was approximately 10% higher. The predominant causative agents were Candida and Aspergillus, at approximately the same rate as in 1989. The rate of candidosis decreased to one-half that of aspergillosis by 1993. Furthermore, severe mycotic infections clearly increased from 58.9% in 1989 to 75.6% in 1997. Among a total of 1000 cases with mycotic infection in those 3 years, acute lymphatic leukemia and acute myeloid leukemia were the major diseases (40.6% and 34.8%, respectively), followed by MDS (26.1%). The reasons for increased rates of aspergillosis and of severe mycotic infection can be surmised to be: (i) candidosis had become controllable by prophylaxis and by empiric therapy for mycoses with effective antifungal drugs; (ii) the marketed antifungal drugs were not sufficiently effective against severe infections or Aspergillus infections; and (iii) the number of patients surviving in an immunocompromised state had increased due to developments in chemotherapy and progress in medical care.

To identify recent trends in the frequency of mycoses in autopsy cases, we analyzed, on a four-year basis, the 1989-2009 data in the Annual of Pathological Autopsy Cases in Japan. Of the 13,787 (9235 males) autopsies conducted in 2009, 4.5% (633/13,787) involved fungal infections and of the latter, 60.3% (368/633) were found to have severe clinical manifestations. Among the 610 (96.4%) cases involving a single etiologic angent, the predominant pathogens were Aspergillus (299 cases; 49%) and Candida (184 cases; 30.2%). However, it should be noted that the prevalence of severe aspergillosis and candidiasis has been decreasing. Although the frequency of cases involving zygomycetes seemed to be generally remaining stable from 1989-2009, we noted for the first time a peak in 2009 in such infections in patients less than one year old. Finally, deep-seated infections caused by unidentified fungi would appear to be decreasing over the time of the survey. Our finding, it is hoped, will encourage physicians to actively pursue viscerial fungal infections.

The data on visceral mycoses reported in the " Annual of Pathological Autopsy Cases in Japan " were analyzed epidemiologically every four years from 1989 to 2005, and in 2007. The frequency rates of visceral mycoses dropped sharply between 1989 (4.5%) and 1994 (3.2%), but by 2001 had risen again and have remained (4.4-4.6%) generally stable since then. The predominant causative agents were Candida and Aspergillus. Although the rate of candidosis showed a gradual decrease, the rate of aspergillosis showed an increase by degrees. Furthermore, the rate of aspergillosis exceeded that of candidosis in 1994, and the difference in the rates between the two conditions apparently further increased until 2001. After 2005, however no changes in this difference were observed. For complicated infections, the incidence of coinfection with Aspergillus and Candida showed a decreasing, and that with Aspergillus and Zygomycetes showed an increasing tendency. Severe infections with Zygomycetes showed a clear increase from 57.4% in 1989 to 88.9% in 2007. Comparing underlying diseases with mycoses in 1989 and 2007, leukemia (including myelodysplastic syndrome) decreased from 26.1% to 18.8% and bacterial infections (including interstitial pneumonia) increased from 11.1% to 22.1%. By age, the highest frequency rate of mycoses was observed in the range of 60-79 years, and the frequency rate of exogenous fungal infections such as aspergillosis, cryptococcosis, zygomycosis and trichosporonosis showed an increasing trend in the less than one-year old group.