James D. MacLowry

Duration of empiric antibiotic therapy in granulocytopenic patients with cancer

Abstract Early initiation of empiric antibiotic therapy in febrile cancer patients has become established practice, but the appropriate duration of antibiotic therapy when no infectious source can be identified is unknown. The complications of broad-spectrum antibiotics argue for brief treatment, but the risk of an inadequately treated infection in the granulocytopenic patient favors longer therapy. We prospectively studied 306 episodes of fever and granulocytopenia in 143 patients with leukemia or solid tumor (age one to 33 years) with respect to the duration of empiric antibiotic treatment. Eligible patients (fever > 38 °C three times/24 hours or > 38.5 °C once, plus polymorphonuclear leukocytes 3 ) had an extensive diagnostic evaluation, including at least two preantibiotic blood cultures, and therapy was then started with a broad-spectrum antibiotic regimen— Keflin ® , gentamicin and carbenicillin (KGC). Initial evaluation failed to identify an infectious etiology for the fever in 142 of 306 (46 per cent) episodes. Fifty-six of 142 (39 per cent) of these fevers of unknown origin were associated with persistent granulocytopenia for more than seven days; in 33 of these, defervescence occurred while the patients received KGC. After seven days of empiric KGC therapy, the 33 patients with fevers of unknown origin who had become afebrile with empiric antibiotics but whose polymorphonuclear leukocytes remained less than 500/mm 3 were randomized to either continue or discontinue (dc) to receive KGC. The patients who continued to receive KGC until their polymorphonuclear leukocytes were more than 500/mm 3 had no infectious sequelae. However, in seven of 17 (41 per cent) of the patients randomized to dc KGC infectious sequelae developed (p = 0.007) within a median of two days of discontinuing KGC (two with fever which again responded to KGC therapy, and five with a documented infection [two ultimately fatal]). In none of the patients did a resistant microbial flora or superinfection develop. These data suggest that the patient with a fever of unknown origin who becomes afebrile during empiric antibiotic therapy may profit from continued therapy while granulocytopenia persists.

Sepsis with a New Species of Corynebacterium

Sepsis with a previously undescribed species of Corynebacterium was documented in four patients. All patients had predisposing illness at the time of infection, three patients having leukemia in relapse and one having a porencephalic cyst and a ventriculoatrial shunt. The isolates from blood cultures had a characteristic metallic sheen when grown on blood agar. They were resistant to most antibiotics tested, including the penicillins, but were uniformly sensitive to vancomycin. Common biochemical characteristics, the metallic sheen, and the unusual antibiotic sensitivity pattern suggest that these isolates comprise a new species or group of closely related species of Corynebacterium that is capable of infection in man.

The relationship of fever, granulocytopenia and antimicrobial therapy to bacteremia in cancer patients

The relationship of fever, granulocytopenia, and antimicrobial thereapy to bacteremia was studied retrospectively in 53 cancer patients. Severe granulocytopenia was present at the time blood cultures were positive in 27 of 31 episodes of bacteremia. Twenty‐five episodes of bacteremia were documented before the initiation of antimicrobial therapy in patients who were granulocytopenic and febrile. No bacteremia occurred in the absence of fever. Only two bacteremias occurred while patients were receiving parenteral antimicrobials. Antimicrobial therapy was terminated 30 times in the presence of granulocytopenia and fever, and subsequent bacteremia occurred in 14 patients within 4 days. Patients who died with fungal disease did not receive more antibiotics than patients who died without fungal disease. These data suggest a rationale for long‐term use of antimicrobial therapy in patients with persistent granulocytopenia and fever.

Metastatic choriocarcinoma of the lung: Invasion of pulmonary veins with extension into the left atrium and mitral orifice

Abstract The clinical and pathologic features of a patient with choriocarcinoma, metastatic to the lungs, with obstruction of the right major pulmonary veins and extension into the left atrium and mitral valvular orifice are described.

Pneumocystis carinii Identified by Gram Stain of Lung Imprints

The diagnosis of Pneumocystis carinii pneumonia conventionally depends on the time-consuming demonstration of the organisms in pulmonary secretions or lung tissue using toluidine blue 0, methenamine silver, or Gram Weigert stains that require special reagents. In 27 recent episodes of moderate to heavy pneumocystis infections, the cyst form and internal sporozoites of P. carinii could be readily identified on lung imprints using the conventional Gram stain. The Gram stain is unlikely to replace special stains for the diagnosis of pneumocystosis, but it does provide a rapid method to recognize moderate to heavy infections.

Clinical microbiology of bacteremia: An overview

Newer methodologies for detecting bacteria in blood are more sensitive than conventional procedures. The possibility of contamination from a variety of sources is discussed. The problem of interpreting the findings of some of these techniques is forcing the microbiologist and clinician to reevaluate previously held ideas regarding isolates that are considered insignificant. The aggressive use of foreign bodies, whether of short duration such as central venous catheters or of long duration such as prosthetic heart valves, predisposes patients to a wide variety of infectious complications that are often associated with bacteremia. Staphylococcus epidermidis, Corynebacterium species (particularly group JK), Bacillus species, and S. aureus are discussed.