Ingo Sobottka

SYSTEMIC PENICILLIUM MARNEFFEI INFECTION IN A GERMAN AIDS PATIENT

Section of Infectious Diseases, Hospital de Galdakao, 48960 Vizcaya, Spain. thrombocytopenic purpura associated with human immunodeficiency virus infection: demonstration of p24 antigen in endothelial cells. Clinical Infectious Diseases 1993, 17: 360-363. 12. Lafeuillade A, Aiessi MC, Poizot-Martin I, Boyer-Newmann C, Zandotti C, Quilichini R, Aubert L, Tamalet C, Juhan-Vague Y, Gastaut JA: Endothelial cell dysfunction in HIV infection. Journal of the Acquired Immune Deficiency Syndromes 1992, 5: 127-131. 13. Salem G, Terebelo H, Raman S: Human immunodeficiency virus associated with thrombotic thrombocytopenic purpura: successful treatment with zidovudine. Southern Medical Journal 1991, 84: 493-495. 14. Routy JP, Beaulieu R, Monte M, Saint-Louis J, Sauvageau G, Toma E: Immunologic thrombocytopenia followed by thrombotic thrombocytopenic purpura in two HIV-1 patients. American Journal of Hematology 1991, 38: 327-328.

Rapid Identification of Bacteria from Positive Blood Culture Bottles by Use of Matrix-Assisted Laser Desorption-Ionization Time of Flight Mass Spectrometry Fingerprinting

ABSTRACT Early and adequate antimicrobial therapy has been shown to improve the clinical outcome in bloodstream infections (BSI). To provide rapid pathogen identification for targeted treatment, we applied matrix-assisted laser desorption-ionization time of flight (MALDI-TOF) mass spectrometry fingerprinting to bacteria directly recovered from blood culture bottles. A total of 304 aerobic and anaerobic blood cultures, reported positive by a Bactec 9240 system, were subjected in parallel to differential centrifugation with subsequent mass spectrometry fingerprinting and reference identification using established microbiological methods. A representative spectrum of bloodstream pathogens was recovered from 277 samples that grew a single bacterial isolate. Species identification by direct mass spectrometry fingerprinting matched reference identification in 95% of these samples and worked equally well for aerobic and anaerobic culture bottles. Application of commonly used score cutoffs to classify the fingerprinting results led to an identification rate of 87%. Mismatching mostly resulted from insufficient bacterial numbers and preferentially occurred with Gram-positive samples. The respective spectra showed low concordance to database references and were effectively rejected by score thresholds. Spiking experiments and examination of the respective study samples even suggested applicability of the method to mixed cultures. With turnaround times around 100 min, the approach allowed for reliable pathogen identification at the day of blood culture positivity, providing treatment-relevant information within the critical phase of septic illness.

Virulence factors of Enterococcus faecalis and Enterococcus faecium blood culture isolates.

Abstract Known and potential virulence factors of enterococcal blood culture isolates were studied using 89 Enterococcus faecalis and 24 Enterococcus faecium isolates. The prevalence of the respective factors was (Enterococcus faecalis vs. Enterococcus faecium): hemolysin 16% vs. 0%, gelatinase 55% vs. 0%, aggregation substance 63% vs. 13%, lipase 35% vs. 4%, hemagglutinin 97% vs. 0%. Deoxyribonuclease was not detected in any isolate. The study showed that hemagglutinin and lipase may represent additional virulence factors of Enterococcus faecalis but not Enterococcus faecium. The significance of these factors in the pathogenesis of enterococcal infection needs to be elucidated in further studies.

In Vitro Activity of Moxifloxacin against Bacteria Isolated from Odontogenic Abscesses

ABSTRACT We evaluated the antimicrobial susceptibility of 87 pathogens isolated from 37 patients with odontogenic abscesses. The most prevalent bacteria were viridans group streptococci and Prevotella species. Considering all bacterial isolates, 100% were susceptible to amoxicillin-clavulanic acid, 98% were susceptible to moxifloxacin and to levofloxacin, 76% were susceptible to doxycycline, 75% were susceptible to clindamycin, and 69% were susceptible to penicillin.

Shiga Toxin-Producing Escherichia coli Infection and Antibodies against Stx2 and Stx1 in Household Contacts of Children with Enteropathic Hemolytic-Uremic Syndrome

ABSTRACT Ninety-five household contacts (aged 2 months to 73 years) of patients with enteropathic hemolytic-uremic syndrome (HUS) were investigated for the presence of immunoglobulin (Ig) G antibodies to Shiga toxins Stx2 and Stx1 by Western blot assay. Thirty-one percent of the household contacts and 19% of 327 controls had anti-Stx2 IgG (heavy and light chain [H + L]), 5 and 8%, respectively, had anti-Stx1 IgG (H + L), and 3 and 2%, respectively, had both anti-Stx2 and anti-Stx1 IgG (H + L). The incidence of infections with Stx-producing Escherichia coli (STEC) was determined based on the following diagnostic criteria: STEC isolation, detection of stx gene sequences, free fecal Stx in stool filtrates, and serum IgM antibodies against E. coli O157 lipopolysaccharide. Evidence of STEC infection was observed in 25 household contacts, of whom 18 (72%) were asymptomatic and represented a potential source of infection. Six of 13 (46%) household contacts with Stx2-producing E. coli O157:H7 in stool culture developed anti-Stx2 IgG (H + L), compared to 71% of Stx2-associated HUS cases. In individuals showing anti-Stx2 IgG (H + L), the antibody response was directed against the B subunit in 69% of household contacts and 71% of controls, in contrast to 28% of HUS patients. In this investigation controls had a significant increase of the median of IgM antibodies to O157 lipopolysaccharide (LPS) with age, up to the fifth decade. The lack of disease in household contacts with B subunit-specific antibodies, as well as the significantly higher median of anti-O157 LPS IgM antibodies in controls beyond 4.9 years of age, suggests a protective role for anti-Stx and anti-O157 LPS antibodies.

ramR Mutations in Clinical Isolates of Klebsiella pneumoniae with Reduced Susceptibility to Tigecycline

ABSTRACT Five Klebsiella pneumoniae isolates with reduced susceptibility to tigecycline (MIC, 2 μg/ml) were analyzed. A gene homologous to ramR of Salmonella enterica was identified in Klebsiella pneumoniae. Sequencing of ramR in the nonsusceptible Klebsiella strains revealed deletions, insertions, and point mutations. Transformation of mutants with wild-type ramR genes, but not with mutant ramR genes, restored susceptibility to tigecycline and repressed overexpression of ramA and acrB. Thus, this study reveals a molecular mechanism for tigecycline resistance in Klebsiella pneumoniae.

Mycobacterium microti Llama-Type Infection Presenting as Pulmonary Tuberculosis in a Human Immunodeficiency Virus-Positive Patient

ABSTRACT A rare case of Mycobacterium microtiinfection in a human immunodeficiency virus-positive patient is described. Because of unusual morphological and cultural features, the pathogen was analyzed by spoligotyping and identified as theMycobacterium microti llama type. Although culture ofM. microti is difficult, drug susceptibility testing could be performed, which correlated with the clinical outcome.

Prevalence and Clinical Significance of Intestinal Microsporidiosis in Human Immunodeficiency Virus-Infected Patients With and Without Diarrhea in Germany: A Prospective Coprodiagnostic Study

The prevalence of intestinal microsporidiosis among human immunodefiency virus (HIV)-infected persons with chronic diarrhea varies from 7% to 50%; thus, microsporidia are a significant source of morbidity and, occasionally, mortality among these patients. Anecdotal reports suggest that intestinal microsporidiosis is also an important infection in patients with AIDS in Germany. To determine the prevalence of microsporidiosis among HIV-infected patients in Germany, we performed a prospective coprodiagnostic study of 97 consecutive HIV-infected patients. Microsporidia were the most common enteropathogen identified in 18 (36.0%) of 50 patients with diarrhea and 2 (4.3%) of 47 patients without diarrhea (P < .001; chi2 test). Microsporidia were present in 60% of patients with chronic diarrhea and 5.9% of patients with acute diarrhea. The etiologic agent was Enterocytozoon bieneusi in 18 patients and Encephalitozoon intestinalis in two patients. The prevalence of intestinal microsporidiosis in this cohort of German patients with AIDS and diarrhea is one of the highest to be reported anywhere in the world. Microsporidiosis seems to represent one of the most important causes of diarrhea in HIV-infected patients in Germany and thus must be considered in the differential diagnosis for all AIDS patients presenting with diarrhea.

Presentation by scanning electron microscopy of the life cycle of microsporidia of the genus Encephalitozoon.

This paper presents, for the first time, documentation by detailed scanning electron microscopy of the life cycle of microsporidia of the genus Encephalitozoon. Phase 1 is represented by the extracellular phase with mature spores liberated by the rupture of host cells. To infect new cells the spores have to discharge their polar filament. Spores with everted tubes show that these are helically coiled. When the polar tubules have started to penetrate into a host cell they are incomplete in length. The infection of a host cell can also be initiated by a phagocytic process of the extruded polar filament into an invagination channel of the host cell membrane. After the penetration process, the tube length is completed by polar tube protein which passes through the tube in the shape of swellings. A completely discharged polar tube with its tip is also shown. The end of a polar tube is normally hidden in the cytoplasm of the host cell. After completion of the tube length the transfer of the sporoplasm occurs and phase 2 starts. Phase 2 is the proliferative phase, or merogony, with the intracellular development of the parasite that cannot be documented by scanning electron microscopy. The subsequent intracellular phase 3, or sporogony, starts when the meronts transform into sporonts, documented as chain-like structures which subdivide into sporoblasts. The sporoblasts finally transform directly into spores which can be seen in their host cell, forming bubble-like swellings in the cell surface.

Streptococcus suis meningitis and septicemia contracted from a wild boar in Germany.

Sirs: A 51-year-old man was admitted to the hospital with dizziness, headache, neck rigidity, nausea, and progressive loss of consciousness. The body temperature was 39.0 °C, white cell count was 20.0x10E9/l (95 % neutrophils), and C-reactive protein was 236 mg/l. Computed tomography (CT) showed brain edema with basal swelling, meningeal contrast enhancement, and dilated ventricles that had to be drained for 10 days. Cerebrospinal fluid (CSF) was turbid with a polymorphonuclear pleocytosis (1,251 cells/μl), protein of 1,924 mg/l, and lactate of 7.2 mmol/l. Gram stain showed pairs and short chains of Grampositive coccoid rods (Fig. 1). Streptococcus pneumoniae meningitis or Listeria meningitis was suspected. Antibiotic treatment consisted of 2 g ceftriaxone, 6 g ampicillin, and 240 mg gentamicin for 14 days. Both blood and CSF cultures (Mueller-Hinton agar, 5 % sheep blood) grew beta-hemolytic streptococci that were identified as Streptococcus suis using ID 32 Strep (bioMérieux, France) (Fig. 2). Serological evaluation by the German national reference laboratory for streptococci (Department of Microbiology, University of Aachen, Germany) identified the isolate as Streptococcus suis type 2, Lancefield group R. There was no evidence of a source of infection such as endocarditis or ear infection, but dental examination revealed a carious molar with a purulent chronic gingival inflammation. During the following days the patient developed septicemia and multiple CT-proven septic-embolic infarctions of the left kidney. After regaining consciousness the patient was found to have bilateral perceptive deafness, and extensive bilateral visual field deficits. As fundoscopy was normal, and CT and magnetic resonance imaging of the brain did not show cerebral lesions that may have been responsible for visual field deficits, septic-embolic infarctions of the optic nerves were suspected. Three months later the patient still suffered from perceptive deafness despite external hearing devices. The binocular visual field deficits had slightly improved. The history of the patient’s lifestyle and habits regarding porcine exposure revealed that he never had contact to domestic pigs. However, the patient was a recreational hunter and had shot and butchered a wild sow two days preceding the onset of clinical symptoms. While butchering the dead wild sow, he accidentally dropped a stick of wood out of his mouth on which he habitually chewed while hunting, intuitively picked it back up, and continued chewing on it. Hence the purulent gingivitis mentioned is the most likely port of entry. Streptococcus suis infection is a porcine zoonosis that may cause meningitis in man [2]. The causative agent is Streptococcus suis type 2, which may be isolated from palatine tonsils of its natural host, the domestic pig [1, 4]. The incidence of Streptococcus suis meningitis in subjects occupationally exposed to domestic pigs has been reported to be 3/100,000, almost 1,500-times higher than among persons not working in the pigrearing industry [2]. However, to our knowledge, only three cases of human infection have been traced to wild boars [3, 5, 6]. Perceptive deafness may be found in up to 67 % of patients with Streptococcus suis meningitis [2, 8, 9] and is suggested to result from cochlear sepsis rather than eighth cranial nerve involvement [7]. Septicemia is a major complication of Streptococcus suis infection [2], but septicembolic infarctions of the kidney and of the optic nerves have not previously been reported. The present report emphasizes LETTER TO THE EDITORS