Streptococcal toxic shock-like syndrome (STSS) was firstly reported in 1987 in the United States. Japanʼs first definitive STSS case was reported in 1992, with over 500 cases since confirmed. Mortality is extremely high at 40％. Pathological findings, bacteria aggregation, and a paucity of polymorphonuclear neutrophils (PMN) in the foci of invasive group A streptococcal (GAS) infection suggest that host defense disturbance plays an important role in invasive infection onset. GAS, clinically isolated from severely invasive, but not from non-invasive, infections, could compromise human PMN functions in at least two independent ways-by inducing necrosis to PMN by enhanced production of pore-forming toxin streptolysin O (SLO) and by PMN migration impairment via digesting interleukin-8, a PMN attracting chemokine, through increased serine protease ScpC production. Expression of these genes was upregulated by a loss of repressive function with the csrS gene mutation of the two-component sensor/regulator system.
A box-lunch-associated food-borne outbreak occurred in Tokyo and Chiba Prefecture in June 2003 involved six types of enterotoxigenic Escherichia coli (ETEC). Fecal specimens from patients were screened for ETEC using colony-sweep polymerase chain reaction (PCR). Of the 84 fecal specimens examined, 56 (66.7％) were PCR-positive, i.e. 35 (41.7％) LT-gene-positive, 21 (25.0％) STp-gene-positive and 11 (13.1％) STh-gene-positive. Both of toxin-genes, i.e. LT and STp, LT and STh, STh and STp were positive in 11 patients. ETEC was isolated in confirmation testing from 48 (57.1％) fecal specimens. A single type of ETEC was isolated from 43 fecal samples. Serotype and toxin type of the isolates were O25 : NM (LT) (21 samples), O 27 : H20 (STp) (12 samples), O148 : H28 (STh) (8 samples), O25 : NM (STh) (1 sample), and O27 : H7 (STp) (1 sample). Two types of ETEC were isolated from 5 fecal samples, i.e. O25 : NM (LT) and O27 : H20 (STp) (3 samples), O27 : H20 (STp) and O148 : H28 (STh) (1 sample), and O25 : NM (LT) and O78 : NM (STh) (1 sample).
Of 95 Tsutsugamushi disease case occurring in Yamagata prefecture from 1999 to 2006, four-all women involved the O. tsutsugamushi Kawasaki serotype. The three major symptoms were fever, exanthema, and eschar present from mid-October to early November. Serodiagnosis by indirect immunofluoresence assay showed elevated IgG and IgM antibody titers against the Kawasaki serotype antigen, with IgM higher than IgG. Nested PCR detected 56-kDa DNA in three of the cases. DNA was amplified in Kawasaki-specific PCR. Two cases for which sequencing was done using nested PCR-amplified DNA showed an identity of 99.8％ for the Kawasaki strain (Accession number : M63383). These results confirmed the occurrence of Tsutsugamushi disease infection involving Kawasaki serotype in Yamagata prefecture.
Psittacosis outbreak due to Chlamydophila psittaci occurred among staff members at an avian exhibition of nearly 1,000 birds in Kobe, Japan, in December 2005. Staff members not trained about zoonosis or psittacosis used little protective attire such as masks and gloves when caring for their discharges. Two of 67 staff members contracted psittacosis pneumonia. Additional two suffered from pneumonia and 19 reported symptoms such as fever and cough, although none were diagnosed with psittacosis. The roughly 970 birds were kept without quarantine and identified by leg bands. Doxycycline administrated in drinking water and food failed to eradicate chlamydia, so all birds were captured, identified by leg band, and tested for chlamydia by PCR. Six were found to carry large amounts of chlamydia. Major outer membrane protein (MOMP) DNA sequence of chlamydia in a patientʼs bronchoalveolar lavage fluid (BALF) was identical to that derived from a channel-billed toucan kept in a closed aviary, and staff members may have been infected by inhaling excrement while working in the aviary. The MOMP DNA sequence was useful in comparing strains. We review the difficulty of diagnosing psittacosis and the knowledge and infection control measures required against it.
The incidence of empyema as a thoracic surgical site infection (SSI) is relating low, but empyema related to MRSA poses an unenviable therapeutic challenge. We review 3 cases of MRSA-related empyema as SSI seem in the last 10 years, and evaluate therapeutic measures. All 3 subjects began being administered vancomycin (VCM) systemically once the diagnosis was established. Subject 1 developed MRSA-related empyema following pulmonary segmentectomy for small-cell lung cancer. The subject was treated following a diagnosis of incisional SSI, with delayed adequate pleural drainage, resulting in treatment difficulties, but was cured without becoming MRSA-negative. Subject 2 developed MRSA-related empyema following pulmonary lobectomy for advanced lung cancer associated with pneumoconiosis. Following bronchoplasty, a chest tube was placed for long-term drainage. The subject did not become MRSA-negative after VCM administration, but became so after linezolid treatment, facilitating a cure. Subject 3, who had secondary pneumothorax, underwent thoracoscopic partial hepatic resection. Intraoperative findings suggested pleural cavity infection, necessitating a prophylactic drain, but MRSA-related pyothorax developed. Fibrinolysis with urokinase effectively cleared up the poor drainage and the subject was cured without becoming MRSAnegative. In conclusion, in controlling MRSA-related empyema as SSI noted that : (1) long-term postperative thoracic drain retention may lead to retrograde infection ; (2) surgical procedures reducing the extent of pulmonary resection may effectively prevent pyothorax progression ; (3) for poor drainage in advanced pyothorax, fibrinolytic therapy is worth attempting before thoracoscopic surgery ; and (4) the timing for discontinuing anti-MRSA drugs should be determined based on the clinical course rather than negative conversion of bacteria.
We compared the performance of two commercial toxin detection kits, C.difficile toxin A/B(C.difficile TOX A/B II test ; TOX A/B II) and C.difficile toxin A (Uniquick), for (i) detection using highly purified toxin A solution ; (ii) cross-reactivity using culture supernatants of toxin A-positive and B-positive C.difficile, toxin A-negative and B-positive C.difficile, and toxin A-negative and B-negative C.difficile strains and other bacteria ; and (iii) sensitivity and specificity using clinical specimens. Results indicated that TOX A/B II detected toxin A at concentrations of 0.35ng/mL and Uniquick at concentrations of 0.7ng/mL. Uniquick performance was specific for detecting toxin A alone, while TOX A/B II detected toxin A/B specifically. Kit performance was then evaluated using 99 fecal specimens -43 specimens from patients with toxin B-positive C.difficile and 56 from those without. Sensitivity of TOX A/B II vs Uniquick was 95.3％ vs 76.7％, specificity 98.2％ vs 98.2％, positive predictive 97.6％ vs 97.1％, and negative predictive value 96.5％ vs 84.6％. Findings thus indicate that TOX A/B II is a more suitable diagnostic aid for CDAD than Uniquick because it correlates well with toxin B-positive C.difficile culture results. Stool culture for C.difficile is also required, however.
Measles hemagglutination inhibition (HI) antibody titer, widely used in clinical practice to simply and easily determine the measles immunity level has, in recent years, been increasingly replaced by measles IgG-antibody titer determined by enzyme-immunoassay (EIA). HI antibody titer appears to reflect this protective level, because HI measures the antibody against H protein required for the measles virus to adhere to host cells. EIA-IgG antibody titer does not correlate with the protective level, similar to particle agglutination (PA) titer, because EIA measures different antibodies,including those unrelated to measles protection. After determining HI, PA, neutralizing test (NT) results, and EIA-IgG antibody titer for individual specimens, we compared EIA-IgG antibody titer obtained using an EIA-Kit （Denka Seiken） to HI, PA, and NT titer with the following results : (1) Subjects with EIA-IgG titer of ≧12.0 may be protected against measles : (2) Subjects with EIA-IgG titer of 4.0 to 8.0 appear to be protected insufficiently requiring a booster dose against measles : (3) Subjects with EIA-IgG titer of 8.0 to 12.0 may benefit from booster vaccination.
Rapid-diagnosis kits able to detect influenza A and B virus by immunochromatography developed by different manufacturers, while useful in early diagnosis, may vary widely in detection sensitivity. We compared sensitivity results for eight virus-detection kits in current use-Quick Chaser FluA, B Ⓡ(Mi zuho Medy), Espline ⓇInfluenza A & B-N (Fujirebio), Capilia ⓇFlu A＋B (Nippon Beckton Dickinson & Alfesa Pharma), Poctem ⓇInfluenza A/B (Otsuka Pharma & Sysmex), BD Flu Examan Ⓡ(Nippon Beckton Dickinson),Quick Ex-Flu Ⓡ“Seiken”(Denka Seiken), Quick Vue ⓇRapid SP Influ (DP Pharma Biomedical), and Rapid Testa ⓇFLU stick (Daiichi Pure Chemicals)-against influenza virus stocks, contained five vaccination strains (one A/H1N1, two A/H3N2, and two B) and six clinical strains (two A/H1N1, two A/H3N2, and two B). Mini mum detection concentrations giving immunologically positive signals in serial dilution and RNA copies in positive dilution in real-time reverse transcriptase-polymerase chain reaction (RT-PCR) were assayed for all kits and virus stock combinations. RNA log10 copy numbers/mL in dilutions within detection limits yielded 5.68-7.02, 6.37-7.17, and 6.5-8.13 for A/H1N1, A/H3N2, and B. Statistically significant differences in sensitivity were observed between some kit combinations. Detection sensitivity tended to be relatively higher for influenza A than B virus. This is assumed due to different principles in kit methods, such as monoclonal antibodies, specimen-extraction conditions, and other unknown factors.
We report a rare case of toxoplasmic encephalitis in a non-AIDS patient. A 62-year-old man undergoing hemodialysis for seven months and corticosteroid therapy for rapidly progressive glomerulonephritis and admitted for generalized convulsions was found in cranial magnetic resonance imaging (MRI) to have multiple ring-enhanced lesions. Antibodies against Toxoplasma gondii, and in Sabin-Feldman dye test were extremely high, yielding a diagnosis of toxoplasmic encephalitis. He was also diagnosed as having cytomegaloviral retinitis. Anti-HIV antibody was negative. Treatment with pyrimethamine and clindamycin was effective and intracerebral lesions disappeared. Physicians encounting a similar situation should consider toxoplasmic encephalitis as a differential diagnosis, even in non-HIV patients, and implement confirmational examination.
A 78-year-old man administered prednisolone and cyclosporin A for bullous pemphigoid and found in computed tomography (CT) to have a left-lung nodule was suspected of having a fungal infection due to elevated blood (1→3)-β-D-glucan. Despite empirical antifungal therapy, however, the nodule grew, followed by new nodules in both lungs. Disseminated nocardiosis was eventually diagnosed based on sputum, blood, and skin cultures growing Nocardia sp. Antinocardial treatment with imipenem/cilastatin and amikacin was started. The patient then developed pneumocystis pneumonia for which pentamidine was added. He had recovered completely when antimicrobial therapy was completed. A wide variety of microorganisms may infect patients with impaired cellular immunity, simultaneously involving multiple organisms in some cases. Definitive microbiological diagnosis with culture or biopsy specimens is therefore crucial for appropriate management.
Streptococcus suis, a major global porcine pathogen, is an emerging zoonosis in Southeast Asia that triggered a 2005 outbreak in China. S. suis causes meningitis, sepsis, and endocarditis in both pigs and humans and involves significant mortality. We report the case of a previously healthy 50-year-old dairy farmer who developed S. suis type 2 endocarditis complicated by pulmonary embolism and spondylitis. He experienced a high fever, chills, fatigue, and worsening low back pain in the 6 weeks prior to admission. On physical examination, he had lumbar spine tenderness and weakness of the left leg. Blood culture identified penicillin sensitive S. suis type 2. Echocardiography showed vegetation on the tricuspid valve, and magnetic resonance imaging (MRI) showed signs of spondylitis. The man reported sudden chest pain several days after admission, which computed tomography (CT) showed what was diagnosed as a septic pulmonary embolism. He was treated with penicillin G for 4 weeks and gentamicin for the first 2 weeks, followed by 2 weeks of oral amoxicillin, after which his symptoms gradually improved. The infection source was probably his dairy herd, since calves often bit his fingers while feeding and S. suis was found in their oral mucus. Over 400 cases of human S. suis infection have been reported globally, but this is, to our knowledge, the first known case of bovine transmission. All of Japanʼs 8 other cases involved occupational swine exposure, 5 of whom had injuries to their fingers. This emerging situation should be made known to all possibly involved in unprotected direct contact with swine and cattle, particularly when the skin could be compromised by cuts or abrasions.
A 40-year-old man undergoing allo-hematopoietic stem cell transplantation for chronic myelogenous leukemia and developing diarrhea was administered prophylactic antibiotics including levofloxacin, fluconazole, cotrimoxazole, and vancomycin. Stool specimens were positive for toxin A in enzyme immunoassay but negative for toxin B in cell culture assay with a neutralization test, indicating that toxin A detection was false-positive. Stool culture yielded enterotoxin producing Clostridium perfringens, not Clostridum difficile. Polymerase chain reaction (PCR) detected the gene encoding C. perfringens enterotoxin in DNA extracted from stool specimens, but not the toxin B gene. Laboratory tests for enterotoxic C. perfingens may therefore be necessary for diagnosing antibiotic-associated diarrhea when culture for C. difficile is negative.
Shewanella algae is an aquatic gram-negative bacterium, rarely recovered from human clinical samples. Case reports of human Shewanella infection are, however, slowly increasing, and a Shewanella infection outbreak was reported at a South Korean hospital. We report the case of an 89-year-old man admitted for back pain and fever after eating raw marine fish. Sulbactam/cefoperazone was started under a tentative diagnosis of gall bladder inflammation with gallstones based on ultrasonographic findings. His persistent back pain,however, necessitated vertebral magnetic resonance imaging (MRI), which showed thoracic vertebral osteomyelitis and discitis. Two sets of blood culture on admission yielded a gram-negative bacillus identified as “Shewanella putrefaciens”by automated identification. Ceftriaxone administration for 3 weeks followed by oral levofloxcin for 5 weeks cured the vertebral osteomyelitis and discitis. 16S rRNA sequence analysis showed that “S. putrefacien”was, in fact, S. algae-incorrectly detected because semi-automated and automated identification did not include S. algae in their database. It should thus be kept in mind that consuming raw-fish may cause Shewanella bacteremia and osteomyelitis in patients with hepatobiliary disease and that genetic analysis is required to precisely determine the occurrence of Shewanella spp.
Domestic animals are the main reservoirs of Pasteurella species for human zoonosis due to bites and scratches. Pasterurella multocida may cause serious soft-tissue infection and, less commonly, sepsis or septic shock, particularly in insufficient initial therapy and an immunocompromised host. We report a case of catscratch-induced P. multocida infection, presenting with disseminated intravascular coagulation and acute renal failure. A febrile 83-year-old woman with consciousness disturbance and a subcutaneous left-foot abscess due to a scratch from a pet cat. She was successfully treated with antibiotic piperacillin and clindamycin therapy and aggressive wound drainage.
Ventriculo-atrial shunt infection (VASI) may lead to sepsis and/or nephritis, making early diagnosis critical. VASI is usually diagnosed by cerebrospinal fluid culture conducted after ventricular puncture or shunt removal, both of which are invasive. Non-invasive attempts at diagnosis, however, present a nonspecific clinical picture unless shunt dysfunction is present. A 57-year-old woman treated with ventriculo-atrial shunt 10 months earlier due to hydrocephalus following subarachnoid hemorrhage developed a fever but evidenced no infected organs in general examination although Staphylococcus epidermidis was isolated several times upon blood culture. Enhanced brain computed tomography (CT) showed neither abnormal findings nor changes in ventricular size and no shunt dysfunction was demonstrated clinically. In cerebrospinal fluid examination, the protein level was 137mg?dL and cell count and bacteriological findings were normal. 10 days later, however, the cell count and bacteriological findings were normal but protein was 180mg/dL. The cerebrospinal fluid protein increase indicated VASI, and the shunt was removed. The womanʼs fever was immediately alleviated and Staphylococcus epidermidis was detected in the cerebrospinal fluid culture of the specimen from the shunt tip and its periphery. Blood culture is useful for identifying bacterial etiology of VASI if neither cerebrospinal fluid cell count increases nor abnormal bacteriological findings are observed, provided that cerebrospinal fluid protein in crease are observed in serial measurement.