Nosocomial infection by human bocavirus and human rhinovirus among paediatric patients with respiratory risks.

BACKGROUND: Nosocomial infections by respiratory viruses undetected by rapid tests are not often diagnosed. For paediatric patients with background diseases, nosocomial infection could be fatal. AIM: To determine the relationship between developing symptoms by respiratory viruses undetectable by rapid tests and respiratory risks and to improve the management of infection control. METHODS: Two episodes of nosocomial infection by human bocavirus (HBoV) and human rhinovirus (HRV) were retrospectively investigated in a tertiary hospital paediatric ward in Japan. Viruses were identified by polymerase chain reaction to determine infection control management. When viruses of the same species were detected from different patients, the virus homology was investigated. The relationship between respiratory risks and developing symptoms was statistically investigated. FINDINGS: Three and four patients with respiratory risks in the HBoV and HRV outbreaks, respectively, developed respiratory symptoms. The nucleotide sequences of two patients in the HBoV outbreak and all four patients in the HRV outbreak were phylogenetically close. In both outbreaks, the patients with respiratory risks developed significantly more symptoms than those without any risk (P = 0.035 and 0.018, respectively). After the patients with respiratory infection were separated from those with respiratory risks, no additional nosocomial infection occurred. CONCLUSION: Patients with respiratory risks easily develop respiratory symptoms and acquire severe symptoms of nosocomial infection by those viruses. In a paediatric ward, we should adopt not only standard precautions but also isolation management of the patients with respiratory symptoms, even if they have negative results in rapid tests.

Associations between capsular serotype, multilocus sequence type, and macrolide resistance in Streptococcus agalactiae isolates from Japanese infants with invasive infections.

SUMMARY Streptococcus agalactiae (group B streptococcus; GBS) isolates (n = 150) from infants with invasive infections between 2006 and 2011 were analysed for capsular serotype, multilocus sequence type, and antibiotic susceptibility. In cases with late-onset disease (n = 115), primary meningitis was predominant (62.6%), but represented only 39.1% in cases with early-onset disease (n = 23). The most common serotype was III (58.7%), followed by Ia (21.3%) and Ib (12.7%). Sequence types (STs) of serotype III strains included ST17 (50.0%), ST19 (26.1%), ST335 (18.2%), ST27 (4.5%), and ST1 (1.1%). Predominant STs of serotypes Ia and Ib were ST23 (81.3%) and ST10 (84.2%), respectively. No penicillin-resistant strains were detected, but 22·0% of strains had mef(A/E), erm(A), or erm(B) genes, which mediate macrolide resistance. A new ST335, possessing an mef(A/E) gene belonging to clonal complex 19 gradually increased in frequency. Improved prevention of invasive GBS infections in infants requires timely identification, and ultimately vaccine development.

Spontaneous pneumomediastinum complicating pneumonia in children infected with the 2009 pandemic influenza A (H1N1) virus.

We report two occurrences of spontaneous pneumomediastinum (SPM) complicating pneumonia in Japanese children infected with the novel influenza A (H1N1) virus (IV). General practitioners especially should suspect possible SPM when examining and treating children with the novel influenza accompanied by status asthmaticus or wheezing. The presented patients illustrate the specific clinical and radiological signs associated with SPM complicating pneumonia in children infected with A(H1N1)v.

Serotype and antibiotic resistance of isolates from patients with invasive pneumococcal disease in Japan.

Invasive pneumococcal disease (IPD) is of concern in Japan, where the heptavalent pneumococcal conjugate vaccine (PCV7) is unavailable. We determined serotypes, genotypes indicating beta-lactam resistance, and antibiotic susceptibilities of 496 isolates from normally sterile sites in patients (193 children, 303 adults) from 186 institutions between August 2006 and July 2007. Disease presentations included sepsis (46.2%), pneumonia (31.5%), and meningitis (17.5%). Mortality was 1.4% in children and 22.1% in adults, many of whom had underlying diseases. In children, serotype 6B (22.5%) was followed by 19F (14.1%), and 14 (13.1%); potential coverages of PCV7 and PCV13 were 75.4% and 93.7%, respectively. In adults, serotype 12F (14.3%) was followed by 3 (11.3%), and 6B (10.3%); 23-valent polysaccharide vaccine (PPV23) coverage was 85.4%. Most serotype 12F strains were gPISP, with pbp2b gene alteration; carbapenem had an excellent MIC90. PCV7 is recommended for children and PPV23 for adults to increase prevention against IPD.

Increased macrolide resistance of Mycoplasma pneumoniae in France directly detected in clinical specimens by real-time PCR and melting curve analysis.

OBJECTIVES: Mycoplasma pneumoniae is a common aetiological agent of community-acquired respiratory tract infections for which macrolides are the treatment of choice. In France, only two macrolide-resistant isolates were reported in 1999. In contrast, several recent data reported that macrolide-resistant M. pneumoniae isolates have been spreading since 2000 in Japan. Mutations A2058G (Escherichia coli numbering), A2058C, A2059G, A2062G, C2611A and C2611G in domain V of the 23S rRNA gene were associated in vivo or in vitro with this resistance. The aim of this study was to determine whether macrolide resistance of M. pneumoniae is emerging in France. PATIENTS AND METHODS: We developed a duplex real-time PCR for the detection of the six 23S rRNA mutations associated with macrolide resistance in M. pneumoniae and a simplex real-time PCR for the identification of the A2058G mutation, the most common one. Both methods rely on fluorescence resonance energy transfer coupled to melting curve analysis and are directly applicable to clinical samples. The duplex real-time PCR assay, first validated on 40 genetically characterized M. pneumoniae strains, was then applied directly on 248 French respiratory tract clinical samples. RESULTS: Among M. pneumoniae-positive specimens collected before 2005, no macrolide-resistant M. pneumoniae isolate was detected. In contrast, among 51 samples collected between 2005 and 2007, five (9.8%) yielded a resistant genotype, suggesting a recent increase in macrolide-resistant M. pneumoniae isolates in France. CONCLUSIONS: The epidemiological monitoring of macrolide resistance in this species has become necessary in France and Europe, and will be made easier by using these PCR assays.

Vitamin B6 deficiency augments endogenous oxalogenesis after intravenous L-hydroxyproline loading in rats.

The effects of an intravenous hydroxyproline load on endogenous oxalogenesis were compared in rats fed a standard diet or a vitamin B6-deficient diet. Twelve male Wistar rats were randomized to two groups and were fed either a standard diet (control group) or a vitamin B6-deficient diet for 3 weeks. Then the animals were intravenously administered 100 mg (762.6 micromol)/ml hydroxyproline. In the control group, infusion of hydroxyproline increased the 5-h urinary oxalate and glycolate excretion above baseline to 0.27% (2.02 +/- 1.11 micromol) and 0.32% (2.43 +/- 1.60 micromol) of the administered dose (mol/mol), while it was respectively 2.01% (15.24 +/- 2.13 micromol) and 0.00% (-0.02 +/- 0.19 micromol) of the dose in the vitamin B6-deficient group. Therefore, vitamin B6 deficiency augmented endogenous synthesis of oxalate from hydroxyproline by 7.56-fold (15.24/2.02) compared with that in the control group. Urinary citrate excretion was significantly lower at baseline and all other times in the vitamin B6-deficient group compared with the control group. In conclusions, L-hydroxyproline loading augmented endogenous oxalogenesis in the vitamin B6-deficient group without causing hyperglycolic aciduria, and also led to significant hypocitraturia. These findings suggest that hydroxyproline is not metabolized to oxalate via glycolate, but rather via the 4-hydroxyglutamate to glyoxylate pathway (usually requiring vitamin B6-dependent enzymes) even in the presence of vitamin B6 deficiency.

Narcolepsy in a hypocretin/orexin-deficient chihuahua.

A two-year-old male chihuahua suffered attacks of muscle weakness and immobility, although it had no family history of paroxysmal attacks. No neurological or blood biochemical abnormalities were recorded when it was first examined. The attacks were typically elicited by stimulation, such as feeding, and a case of sporadic narcolepsy-cataplexy was therefore suspected. Treatment orally three times a day with 1 mg/kg imipramine, was effective in reducing the attacks. The concentration of hypocretin-1/orexin A in the dog's cerebrospinal fluid was less than 80 pg/ml (22.5 pmol/litre), compared with normal canine levels of 250 to 350 pg/ml (70.0 to 98.3 pmol/litre), supporting a diagnosis of hypocretin-deficient narcolepsy.

Diffuse leptomeningeal malignant histiocytosis in the brain and spinal cord of a Tibetan Terrier.

An 8-year-old male Tibetan Terrier showed prolonged astasia, complete paralysis, ticlike signs, and seizure and died 2 months after the onset of symptoms. Histopathologically, there was moderate to severe infiltration of pleomorphic histiocytic mononuclear cells bilaterally in the basiarachnoidal and ventricular areas of the brain. The spinal dura mater, arachnoidal space, and leptomeninges were also affected by infiltrative proliferation of these mononuclear cells. The infiltrating cells had the morphologic characteristics of histiocytes but exhibited moderate pleomorphism and atypia, with abundant mitotic figures. With immunohistochemistry and lectin histochemistry, most of the infiltrating cells were positive for lysozyme and lectin RCA-1 and negative for glial fibrillary acid protein, suggesting that they were of monocytic/histiocytic-origin. Positive proliferating cell nuclear antigen immunostaining demonstrated that most nuclei of the histiocytic cells were in the S phase of the cell cycle, consistent with a proliferating population of cells. Based on these findings, the case was diagnosed as diffuse leptomeningeal malignant histiocytosis.

Impact of dietary calcium and oxalate ratio on urinary stone formation in rats.

BACKGROUND AND PURPOSE: Calcium interferes with oxalate absorption in the gut. We studied stone formation in rats fed diets containing various amounts of oxalate and calcium. MATERIALS AND METHODS: In one experiment, male Wistar rats were fed one of five experimental diets: basal diet (292 mM calcium + 8 mM oxalate) or basal diet plus either 100, 300, 500, or 1000 mM oxalate. In the other experiments, rats were given one of five diets: calcium-free diet alone or calcium-free diet plus 300 mM oxalate and either 0, 100, 200, or 300 mM calcium. Urine specimens were collected every week up to week 4. The kidneys were examined for stone formation and used for determination of tissue oxalate concentration by ion chromatography. Calcium and magnesium were measured by atomic absorption spectrophotometry. RESULTS: The higher the amount of oxalate in relation to calcium in the diet, the higher the urinary oxalate excretion. A low calcium level in the intestine enhanced the uptake of oxalate, leading to hyperoxaluria and calcium oxalate stone formation. CONCLUSION: The bioavailability of dietary oxalate in rats depends mainly on the relative intestinal calcium level. Hyperoxaluria without hyperabsorption of calcium could be induced by oral administration of a relatively high-oxalate and low-calcium (oxalate:calcium >1 [mol/mol]) diet. Exaggerated hyperabsorption of oxalate persists for several weeks and leads to calcium oxalate urolithiasis.

Ascorbate conversion to oxalate in alkaline milieu and Proteus mirabilis culture.

BACKGROUND AND PURPOSE: Ascorbate breakdown reportedly accounts for 30% to 55% of urinary oxalate excreted. Three potential degradation routes can be postulated: bowel, endogenous, and urinary. Because the pH of normal urine ranges from 4.5 to 8.0, the urinary oxalate concentration in the presence of ascorbate may be influenced by urinary pH and environment, so we studied ascorbate conversion to oxalate in standard buffer solution and in urine. About 10% of infection stones associated with Proteus mirabilis are reportedly composed of calcium oxalate, and their pathogenesis is not well explained. Therefore, we studied whether a pH change induced by P. mirabilis contributes to ascorbate conversion to oxalate in vitro. RESULTS: Oxalate production from ascorbate increased as a function of pH (7.0-10.0) and incubation time (30 minutes-24 hours) in standard and urine specimens. Two-hour exposure to pH 10 in a urinary milieu containing approximately 3 mM ascorbate converted approximately 40% of the ascorbate to oxalate, whereas 24-hour exposure to pH 8 in a urinary milieu that was approximately 3 mM ascorbate converted approximately 20% of the ascorbate to oxalate. The pH in Proteus cultures increased to 9.0 at 24 hours of culture. The ascorbate concentration in the culture medium significantly decreased at 12 hours and 24 hours, and the oxalate concentration increased significantly at 24 hours. CONCLUSION: Urinary ascorbate, if present at a high concentration in association with Proteus mirabilis infection, appears to be locally degraded to oxalate, potentially leading to calcium oxalate deposition on infection stones.

Urinary oxalate, glycolate, glyoxylate, and citrate after acute intravenous administration of glyoxylate in rats.

BACKGROUND AND PURPOSE: Urinary oxalate plays an important role in the formation of calcium oxalate renal stones, and approximately 50% to 60% of urinary oxalate is derived from the endogenous metabolism of glyoxylate. Therefore, we measured urinary oxalate, glycolate, glyoxylate, and citrate concentrations after acute intravenous administration of various doses of glyoxylate in rats to study oxalate metabolism. MATERIALS AND METHODS: Male Wistar rats weighing approximately 200 g were divided into six groups of eight animals each. Anesthetized rats received glyoxylate (0, 1, 2, 5, 10, and 20 mg) intravenously. Urine specimens were collected before and every hour after each dose for 4 hours, and the concentrations of oxalate, glycolate, glyoxylate, and citrate were measured by capillary electrophoresis. RESULTS: Hourly oxalate excretion in the urine peaked at 1 hour after glyoxylate administration, and the peak concentration increased in a dose-dependent manner. Approximately 15% to 30% (mol/mol) of the dose was converted to oxalate within 4 hours and 2% to 4.6% was converted to glycolate. Urinary glyoxylate was not detectable before glyoxylate administration, but large doses resulted in a significant amount of glyoxylate (0.7%-2.3%) appearing in the urine, and the level peaked at 1 hour after administration. Urinary glycolate also peaked at 1 hour after administration of glyoxylate. The urinary citrate concentration generally decreased by 3% to 33% after each dose of glyoxylate, except that it increased slightly after the 20-mg dose. CONCLUSION: Administration of glyoxylate increased urinary oxalate and glycolate excretion in rats, supporting the importance of the glycolate-glyoxylate-oxalate pathway.

Distal ureteral atresia associated with crossed renal ectopia with fusion: recovery of renal function after release of a 10-year ureteral obstruction.

We report on a 10-year-old boy with distal ureteral atresia associated with crossed renal ectopia with fusion. He was admitted with a high fever associated with a urinary tract infection. The diagnosis was established by antegrade and retrograde pyelography. The upper hydronephrotic portion of the kidney, obstructed for 10 years, recovered its function after nephrostomy placement. To our knowledge, this is the first patient whose renal function has recovered despite an ureteral obstruction of 10-years' duration. Therefore, we recommend a transient nephrostomy placement even for far advanced pediatric hydronephrosis, to test for the possibility of functional recovery.

Computed tomography and magnetic resonance findings in two dogs and a cat with intracranial lesions.

Two dogs and a cat with intracranial lesions were evaluated by both computed tomography (CT) and magnetic resonance (MR) imaging. In a dog with vestibular syndrome, better quality images of the medulla oblongata surrounded by thick bones were obtained by MR than by CT, on which the appearance of artifacts impeded the clear image of the area. In a dog with multiple brain metastases of lymphoma, contrast CT delineated lesions more clearly than MR, which was performed one week after CT. During that week dexamethasone which might affect the clarity of MR images of the lesion was administered to reduce brain edema. In a cat with meningeal syndrome of lymphocytic leukemia, only contrast MR imaging identified the width and site of the lesion. These results indicate that it is necessary to select either one of these imaging methods according to the type and site of lesions that are suspected in a particular case.

Treatment of canine intervertebral disc displacement with chondroitinase ABC.

STUDY DESIGN: This study demonstrated the therapeutic value of chemonucleolysis with chondroitinase ABC to canine intervertebral disc displacement. OBJECTIVES: To determine the efficacy of Chondroitinase ABC in the management of canine intervertebral disc displacement. SUMMARY OF BACKGROUND DATA: No previous study has assessed the chemonucleolysis with chondroitinase ABC in the displaced discs. The changes of intervertebral disc syndrome were evaluated in this study. METHODS: Fifty-nine dogs with symptoms and signs of intervertebral disc displacement were treated with Chondroitinase ABC by a single intradisc injection. The changes in symptoms and signs of disc herniation in the dogs were followed from 7 days to 3 years after treatment. RESULTS: Forty-eight dogs were evaluated for the efficacy of the chemonucleolytic treatment with chondroitinase ABC. At 1 week after injection, 45 of 48 dogs showed some improvement in symptoms and signs. No adverse reactions were observed. There was no recurrence of symptoms in nine dogs who were observed from 14 months to 3 years after injection. CONCLUSION: Chemonucleolytic treatment with chondroitinase ABC is an effective and safe method for the management of canine intervertebral disc displacement.

Antiviral activities of nucleotide heterodimers against human immunodeficiency virus type 1 in vitro.

Nucleotide heterodimers were synthesized and examined for their inhibitory effects on the replication of human immunodeficiency virus type 1 (HIV-1), including HIV-1 reverse transcriptase (RT) inhibitor-resistant mutants. 3'-Azido-3'-deoxythymidilyl-(5')-phospho-(5')-6-[(3', 5'-dimethylphenyl)thio]-5-ethyl-1-[(2-hydroxyethoxy)methyl]uracil (AZT-P-E-HEPU-dM) and 3'-azido-3'-deoxythymidilyl-(5')-phospho-(5')-2', 3'-dideoxyinosine (AZT-P-ddI) proved to be highly potent and selective inhibitors of HIV-1 (IIIB strain) in MT-4 cells. The mechanism of inhibition by these heterodimers may be attributed to their degradation and the formation of each constituent. AZT-P-E-HEPU-dM was also markedly inhibitory to an AZT-resistant mutant (HIV-1-IIIB/AZT) and an E-HEPU-dM-resistant mutant (HIV-1-IIIB-R). However, AZT-P-ddI was found to have a less inhibitory effect on HIV-1-IIIB/AZT than on HIV-1-IIIB. The heterodimers of (5',5') AZT and ribavirin (AZT-P-Ribavirin) and (5',5') ddI and ribavirin (ddI-P-Ribavirin) were also synthesized: AZT-P-Ribavirin inhibited HIV-1 replication, but ddI-P-Ribarvirin did not.

[The effect of the oxalate precursors on experimental calcium oxalate urolithogenesis in rats: acute and chronic administration].

Glycolate and glyoxylate, documented lithogenic precursors of oxalate, were administered acutely and chronically to Wistar-strain rats in order to study their effects on oxalate excretion and subsequent stone formation. Urinary oxalate increased significantly within 4 hours, with a maximum being reached between 4-8 hours after a single administration of glycolic acid (200 mg) or glyoxylic acid (200mg). The 24-hour increase in urinary oxalate was about 3% of each amount given. Hyperoxaluria developed immediately and persisted throughout the experimental period in all the rats, which were fed on a diet containing glycolic acid or glyoxylic acid at a 3% level. Microscopically amorphous substances accumulated in the renal tubules at one week. Significant crystal formation appeared in the tubules after two weeks in both experimental groups and consistently increased both in number and in volume until the 4th week. Therefore, the oral administration of either glycolate or glyoxylate increased urinary oxalate comparably much within a few hours, but a few weeks of hyperoxaluria may be necessary to develop crystals in the convoluted tubules.

Computed tomography and magnetic resonance findings of meningeal syndrome in a leukemic cat.

A 3-year-old Japanese domestic cat with a diagnosis of lymphocytic leukemia showed severe generalized seizures in the course of chemotherapy after leukemic condition was improved clinically. Computed tomography (CT) and magnetic resonance (MR) imaging of the brain were carried out. Both contrast procedures disclosed enhancements at the falx cerebri and the margin of cerebral cortex. Among these procedures contrast MR imaging demonstrated the lesion most clearly. Cytological examination of cerebrospinal fluid obtained by spinal puncture showed the infiltration of malignant cells and the diagnosis of meningeal syndrome associated with lymphocytic leukemia was defined. Intrathecal administration of cytosine arabinoside partially improved the neurologic dysfunction. Autopsy and histopathological examination confirmed the infiltration of leukemic cells in the areas of meningeal lesion demonstrated with contrast CT and MR imaging. Thus these imaging techniques, especially contrast MR imaging, are useful tools for rapid and precise diagnosis of meningeal syndrome.

[Primary non-Hodgkin lymphoma of the prostate: a case report].

A 24-year-old man presented with gross hematuria and pain on micturition. Cystoscopically the prostatic urethra appeared to be pale, edematous and partly elevated mucosa, from which multiple biopsy specimens were taken by TUR-P. A pathological diagnosis of malignant lymphoma (diffuse and large-cell type, according to the LSG classification: B-cell origin according to immunohistochemistry) was established. The results of the physical examination and imaging studies were compatible with the diagnosis of primary lymphoma of the prostate. The patient underwent a combination chemotherapy consisting of vincristine, cyclophosphamide, adriamycin and prednisolone. After completion of 6 courses of chemotherapy over 7 months, another TUR biopsy of the prostate confirmed complete remission. Now, 1 year after completion of chemotherapy, he remains free of the disease. To our knowledge, this is the 21st clinical case of lymphoma of the prostate ever reported in the Japanese literature.