Fulminant Streptococcus suis infection detected on peripheral blood smear: A case report.

Streptococcus suis, a gram-positive coccus, is recognized as an emerging zoonotic pathogen that causes serious infections in humans, such as bacterial meningitis and sepsis, with poor outcomes. The pathogen is known to be transmitted through the consumption of raw pork or occupational exposure to pigs. A previously healthy 38-year-old woman with occupational exposure to raw pork was presented to our emergency department with a clinical diagnosis of rapidly progressive septic shock. Peripheral blood smears detected chains of cocci inside granulocytes, which led to the early recognition of gram-positive cocci in short chains before the blood culture test results. Blood cultures later tested positive for S. suis serotype 2. The patient's condition deteriorated despite aggressive resuscitative measures including antibiotics, vasopressors, multiple blood transfusions, mechanical ventilation, and renal replacement therapy. Initiation of veno-arterial extracorporeal membrane oxygenation was ineffective, and the patient died 16 h after admission. The identification of bacteria in the peripheral blood smear indicated an overwhelming infection and led to the rapid recognition of bacteremia. Our report aims to raise awareness about fatal zoonotic pathogens and to promote the unique role of peripheral blood smears that could provide preliminary diagnostic information before blood culture results.

The first case report of infective endocarditis caused by Gemella taiwanensis.

Gemella is a facultative anaerobic Gram-positive coccus and a rare cause of infective endocarditis (IE). Gram staining may eventually misidentify the organism, which tends to easily decolorize and manifest as either Gram-negative or Gram-variable. Commercial biochemical tests are often used to identify Gemella, but the methods they employ sometimes lack accuracy. A 52-year-old woman was diagnosed with Gemella taiwanensis IE after initial identification of the pathogen as Gemella haemolysans using biochemical tests combined with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). She was treated successfully with penicillin, gentamicin, and mitral valve replacement. To our knowledge, this is the first case of IE confirmed by 16S rRNA gene and groEL sequencing to have been caused by G. taiwanensis. The accurate diagnosis of rare or difficult-to-identify pathogens is a major challenge for clinical microbiological laboratories. The concurrent use of molecular methods could lead to the recognition of new or different pathogens.

Reappraisal of the serum (1-->3)-beta-D-glucan assay for the diagnosis of invasive fungal infections--a study based on autopsy cases from 6 years.

BACKGROUND: The prevalence of invasive fungal infection is increasing. An effective diagnostic test is required to identify and treat them successfully. METHODS: All autopsy records at our hospital for the period from January 2000 through December 2005 [corrected] were reviewed for cases of invasive fungal infection. The diagnostic efficacy of a serum (1-->3)-beta-D-glucan (beta-glucan) assay was examined using only those cases in which patients had been tested for fungal infection within 2 weeks before death. RESULTS: Of 456 autopsies, 54 (11.8%) involved cases of invasive fungal infection. Leukemias were the most frequent underlying disease (in 52% of cases of invasive fungal infection), and Aspergillus species was the most frequent pathogen detected (in 70%). Of the 54 patients with invasive fungal infection, 41 had beta-glucan testing performed within 2 weeks before death, as did 63 patients without invasive fungal infection; 48 of 54 patients with invasive fungal infection had a blood culture performed. The sensitivity and specificity of the beta-glucan test for the detection of invasive fungal infection were 95.1% and 85.7%, respectively, with a cutoff value of 30 pg/mL; 85.4% and 95.2%, respectively, with a cutoff value of 60 pg/mL; and 78.0% and 98.4%, respectively, with a cutoff value of 80 pg/mL. The sensitivity of blood culture testing was 8.3%. With a prevalence of 11.8%, the positive and negative predictive values for the beta-glucan test were 47.1% and 99.2%, respectively, with a cutoff of 30 pg/mL; 70.4% and 98.0%, respectively, with a cutoff of 60 pg/mL; and 86.7% and 97.1%, respectively, with a cutoff of 80 pg/mL. During the 6-year period studied, of 21 patients with fungus-positive blood cultures that were preceded or followed by a beta-glucan test within 2 weeks, 4 had negative beta-glucan test results (beta-glucan level, <30 pg/mL), and 17 had positive results (beta-glucan level, >60 pg/mL); the concordance between culture results and beta-glucan test results was 81.0%. Contrary to the general belief, 5 of 6 cases of cryptococcemia were associated with high serum beta-glucan levels. CONCLUSION: The beta-glucan test is an effective diagnostic tool for invasive fungal infection.

Frequent exacerbation of pulmonary nocardiosis during maintenance antibiotic therapies in a hematopoietic stem cell transplant recipient.

We describe a rare case of recurrent pulmonary nocardiosis (PN) in a hematopoietic stem cell transplant recipient. The patient developed Nocardia farcinica infection while receiving corticosteroid and cyclosporine for the treatment of bronchiolitis obliterans, probably due to chronic graft-versus-host disease (cGVHD). The patient responded well to the initial treatment with meropenem, but PN recurred 3 times during oral maintenance therapies using different antibiotics, which were chosen on the basis of the results of in vitro susceptibility testing against N farcinica Minocycline, amoxicillin/clavulanate, and levofloxacin were not effective as oral maintenance therapies. Frequent exacerbation of PN was considered to have resulted from the low blood concentration of these antibiotics, and decreased gastrointestinal absorption, probably due to cGVHD, might have been the underlying problem.

[Successful treatment with voriconazole for disseminated cutaneous and visceral infection by Fusarium solani in a patient with acute myeloid leukemia].

We report the successful treatment of a disseminated Fusarium infection with skin manifestations in a severely neutropenic patient. A 51-year-old man with acute myeloblastic leukemia (M4) underwent two courses of remission induction therapy with cytarabine and daunorubicin. Despite prophylactic treatment with tosufloxacin and micafungin, the patient developed a febrile scrotal ulcer. Eight days later, we noted the appearance of painful and diffuse cutaneous nodules and a plain chest X-ray disclosed multiple nodular lesions. Microbiological examination of the scrotal ulcer revealed infection by Fusarium solani, which was also confirmed by both histological and microbiological examination of the skin nodules. Although the patient was treated with amphotericin B (AMPH-B), the clinical symptoms worsened. After AMPH-B was replaced with voriconazole (VRCZ), the patient's symptoms and chest radiographic findings dramatically improved. Thus, VRCZ might be an alternative therapy for patients with neutropenia who have fusariosis that is refractory or unresponsive to AMPH-B.

[Detection of acute HIV infection by serum HIV-1 RNA quantification].

To assess the merit of serum HIV-1 RNA quantification in detecting acute HIV infection, we reviewed the results of HIV-1 RNA assay and antibody tests in all patients who received those tests at our hospital from August 1999 to December 2004. Of 3530 such patients, five were sero-negative and PCR-positive with more than 105 copies/ml at initial examination. Four of them had HAART and followed a favorable course; they were later confirmed to be sero-positive by Western blotting. The other one, positive only by CLEIA, was lost to follow-up. This reconfirms the importance of using PCR in the initial assessment of HIV infection in high-risk patients.