a b s t r a c tIn most terrestrial environments, our knowledge of the elemental composition and stoichiometry of microorganisms stems from indirect whole community analyses. In contrast, we have little direct knowledge of the elemental composition of specific microorganisms and the variation between and within Fungi and Bacteria. To address this issue, we isolated and identified the elemental content of 87 strains of Fungi and Bacteria isolated from grassland leaf litter. The isolated strains were affiliated with a broad range of diversity including Ascomycota and Basidiomycota for Fungi, and Proteobacteria, Bacteroidetes, and Actinobacteria for Bacteria. The C:P and C:N but not N:P ratios were significantly higher in Fungi than in Bacteria. Extensive strain variation in elemental composition was partly linked to phylogeny and growth rate. Across all strains, the geometric mean C:N:P was 88:15:1. This overall ratio was significantly higher than reported for other leaf litter and terrestrial whole communities but closer to the canonical Redfield ratio characterizing marine microorganisms. This result warrants further investigation into the discrepancy between whole community and isolated strain elemental ratios.

Cryptococcal meningitis is a recognized complication of systemic lupus erythematosus (SLE), with high mortality rates, particularly in those treated with immunosuppressive agents. We describe a patient diagnosed simultaneously with cryptococcal meningoencephalitis and SLE and reviewed four similar cases reported in the literature. In our case, profound low CD4 lymphocyte count and low complement levels were observed. The patient was treated with prednisolone, fluconazole, and 5-flucytosine and evinced good clinical improvement. This case suggests that intrinsic immunological abnormality related to SLE predisposed to opportunistic infections.

A 53-year-old woman with systemic lupus erythematosus presented with a 3-day history of fever and coughing. Diagnosis of pneumococcal bronchitis was made based on symptoms and positivity of pneumococcal urinary antigen test. On day 3, severe low back pain acutely occurred. Pneumococcal vertebral osteomyelitis and psoas abscess was diagnosed 17 days later by yield of penicillin-susceptible S. pneumoniae strain in blood cultures and drainage fluid. Although pneumococcal urinary antigen test is a useful tool for the diagnosis of pneumococcal pneumonia, we should consider the possibility of pneumococcal infections other than pneumonia or overwhelming bacteremia in immunosuppressive patients when urinary antigen test is positive.

Cryptococcal meningitis is a recognized complication of systemic lupus erythematosus (SLE), with high mortality rates, particularly in those treated with immunosuppressive agents. We describe a patient diagnosed simultaneously with cryptococcal meningoencephalitis and SLE and reviewed four similar cases reported in the literature. In our case, profound low CD4 lymphocyte count and low complement levels were observed. The patient was treated with prednisolone, fluconazole, and 5-flucytosine and evinced good clinical improvement. This case suggests that intrinsic immunological abnormality related to SLE predisposed to opportunistic infections.

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