Sharon M. Smith

Saccharomyces cerevisiae infections in man

Saccharomyces cerevisiae is a yeast commonly used to make food products such as bread, beer and wine, or ingested whole as a health food. We report five cases of infections involving S. cerevisiae, including one in which S. cerevisiae alone was implicated, and review the literature on its pathogenicity.

Syndrome of severe skin disease, eosinophilia, and dermatopathic lymphadenopathy in patients with HTLV-II complicating human immunodeficiency virus infection

Two intravenous drug users dually infected with human immunodeficiency virus type 1 (HIV-1) and human T-cell leukemia virus type II (HTLV-II) developed an unusual severe dermatitis characterized by progressive brawny induration, fissuring, and ulceration of the skin, with an associated CD8 cell infiltration in one patient. Both patients had persistent eosinophilia. Lymph node biopsy revealed dermatopathic lymphadenopathy, an unusual pathologic finding in HIV-1 infection but one seen in association with mycosis fungoides and other skin disorders. Two new isolates of HTLV-II virus were established from these patients and were identified as HTLV-II by Southern blotting. This type of skin disease and lymph node pathology has not been found in other intravenous drug users who have been infected with HIV-1 alone or in patients in other risk groups for HIV-1 infection. HTLV-II may play a role in this unique new disease pattern in patients infected with HIV-1.

Effectiveness of antibiotic removal by the antibiotic-binding blood culture systems

The effectiveness of antibiotic removal by the BACTEC aerobic resin-containing blood culture medium (16B) and the Antimicrobial Removal Device (ARD) was compared for 12 antibiotics: ampicillin, cephalothin, cefoperazone, cefotaxime, moxalactam, nafcillin, gentamicin, tobramycin, azlocillin, mezlocillin, piperacillin, and ticarcillin. The ability to recover eight commonly encountered species of bacteria from antibiotic-containing serum by these two systems showed that recovery of antibiotic-exposed bacteria was dependent not only upon the amount and rate of the antibiotic removal but also upon the kinetics of bacterial killing by the antibiotic(s). The 16B medium had difficulty recovering organisms exposed to ticarcillin and moxalactam, whereas the ARD had difficulties with moxalactam and sometimes with cefotaxime and cefoperazone. Although neither system was able to recover all species of microorganisms tested, these in vitro results suggest that to use optimally these new culture systems, knowledge of the suspected pathogen(s), the amount and kind of antibiotic(s) administered, and the rate of bacterial killing by the antibiotic(s) is required.

Recovery of blood-borne bacteria from human urine.

Recovery from the urine of organisms causing bacteraemia may depend on the bacterial species involved. The survival of the more common species of bacteria which cause bacteraemia was examined in human urine, serum and normal saline. All species survived well or grew in serum. Haemophilus influenzae, Streptococcus pneumoniae, Streptococcus sanguis and group A streptococci were killed in all urine samples. The number of colony-forming units of Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus and group B streptococci either remained the same or increased in the urine, while the numbers of Escherichia coli and Klebsiella pneumoniae increased rapidly. These data suggest that the observed differences in recovery from urine of these bacterial species that cause bacteraemia are related to the viability of the species in human urine.

Drug-resistance encountered in the retreatment of Mycobacterium tuberculosis infections.

Patients who had prior anti-tuberculosis medications for pulmonary tuberculosis and who return to the hospital with culture-positive tuberculosis have been considered to be at risk of harboring resistant bacilli (secondary resistance or acquired resistance). The present recommendation for therapy of these patients is to resume earlier anti-tuberculosis medications and to add two new agents until the drug susceptibilities of the bacilli are known. This study reviewed 112 cases of readmissions for active tuberculosis and evaluated the risk of acquired drug resistance in this group. Patients with 6 months or less of prior therapy rarely harbored resistant organisms. Patients with 6-12 months of prior therapy had an 88% possibility of harboring resistant bacilli, but only a 30% risk of harboring multiple-drug resistant bacilli. Patients with 12 months or more of prior therapy had a 66% risk of harboring multiple-drug resistant, difficult-to-treat bacilli. This data would indicate that only those patients who have had prior therapy for 7 months or more require aggressive initial readmission therapy with 4 or more anti-tuberculosis agents. Hopefully this finding will not only help clinicians to identify readmission tuberculosis patients who are at increased risk of harboring resistant organisms but will also help them to be more selective in prescribing aggressive, potentially toxic, multiple-drug regimens.