Ming-Fang Cheng

Cryptococcus laurentii Fungemia in a Premature Neonate

ABSTRACT Cryptococcus spp. other than Cryptococcus neoformans are generally considered nonpathogenic to humans. There are only 15 case reports of disease in humans caused byCryptococcus laurentii infection. Underlying diseases and predisposing risk factors seem to play an important role in these cases. Our patient is the first case of an extremely low birth weight infant with C. laurentii fungemia reported in the English literature. In our case, the MIC of amphotericin B for C. laurentii was 0.25 to 1 μg/ml and the patient had a good outcome following the administration of amphotericin B at 10 mg/kg combined with central venous catheter removal. There will undoubtedly be an increasing occurrence of unusual fungal infections accompanying further advances in medicine. A high degree of suspicion and improvements in the techniques for culture and identification will contribute to the earlier diagnosis and treatment of unusual fungal infections.

Acute Community-acquired Osteoarticular Infections in Children: High Incidence of Concomitant Bone and Joint Involvement

BACKGROUND/PURPOSE Pediatric acute osteoarticular infections remain a challenging clinical issue for physicians. This paper provides recent clinical experiences on acute community-acquired osteoarticular infections in children in Taiwan. METHODS Children with acute community-acquired osteoarticular infections admitted to hospital were retrospectively reviewed and the findings compared with related infections in Taiwan published during the past 10 years. RESULTS We enrolled 27 children in our study, and reviewed 692 patients reported from six major studies in Taiwan. Of the 27 patients, 15 (55.6%) had concomitant bone and joint involvement. Blood cultures were positive in 44.4% of the children in this study and 48-52% in the other studies. Pathogens could be identified in 66.7% of our children and 63-76% in the other studies, when surgical specimens were available for culture. Staphylococcus aureus was consistently the most common pathogen found in all studies. Of the S. aureus isolates, methicillin-resistant S. aureus accounted for 13.3% in our study and 22-24% in the others. CONCLUSION Concomitant osteomyelitis and septic arthritis occurred in over half of our patients. The long-term effect of combined bone and joint infection on bone growth remains to be determined. Surgical intervention remains an important component of management of osteoarticular infections. Our findings are consistent with current recommendations of aggressive microbiology diagnosis and initiation of empirical monotherapy with oxacillin or oxacillin plus an agent effective against Gram-negative bacteria in most cases of community-acquired osteoarticular infections.

Emergence of extended spectrum-β-lactamase-producing Escherichia coli O25b-ST131: a major community-acquired uropathogen in infants

Background: Escherichia coli sero-group O25b-sequence type 131 (O25b-ST131), a multidrug-resistant clonal group, is a significant pathogen in adults and children. This study investigated the genotyping and role of extended spectrum &bgr;-lactamase (ESBL)-producing E. coli O25b-ST131 and non-O25b-ST131 in urinary tract infections in infants. Methods: Clinical and laboratory data from 111 infants less than 1 year of age, who were hospitalized for urinary tract infections caused by ESBL-producing E. coli between 2009 and 2012 were collected. Polymerase chain reactions and multi-locus sequence typing were used to identify E. coli O25-ST131 clones. The gene blaCTX-M groups 1, 2 and 9, a specific polymerase chain reaction of CTX-M 14 and 15, were also determined in ESBL-producing E. coli isolates. Results: O25b-ST131 accounted for 65% of the 111 isolates, although 92 isolates belonged to the blaCTX-M group 9, of which most were CTX-M-14. Those with O25b-ST131 clones had similar risk factors, clinical features and outcomes as those with non-O25b-ST131. The E. coli O25b-ST131 isolates were more resistant to ciprofloxacin and gentamicin, but more susceptible to cefoxitin, minocycline and trimethoprim/sulfamethoxazole than the non-O25b-ST131 isolates. Most of the infants (78%) were previously healthy with no apparent risk factors. Conclusions: E. coli O25b-ST131 is a major community-acquired uropathogen in the infant population. Regardless of O25b-ST131 or non-O25b-ST131 clones, CTX-M-14 accounts for majority of the ESBL genotype. The O25b-ST131 clone is not associated with more severe clinical disease, but it may make the diagnosis and selection of antimicrobials for treatment more challenging.

Infective endocarditis in children without underlying heart disease

BACKGROUND/PURPOSE Although pre-existing heart disease is the main predisposing factor for pediatric infective endocarditis (IE), cases of IE in children without underlying heart disease have been increasingly reported. This study reviews the clinical and laboratory characteristics of pediatric IE patients with and without underlying heart disease, and presents the unique features of patients with no apparent pre-existing heart disease. METHODS Children who were admitted to our hospital from January 1991 to April 2011 and met the Modified Duke criteria for definite or possible IE were retrospectively analyzed. Clinical characteristics and laboratory data were collected by chart review. RESULTS Forty-seven patients with a total of 48 episodes of IE were enrolled. Of these patients, 31 children (64.6%) had congenital heart disease (CHD), six (12.5%) had non-CHD chronic disease, and eleven (22.9%) were previously healthy adolescents. Five patients with non-CHD chronic conditions acquired infection from central catheter: two methicillin-resistant Staphylococcus aureus (MRSA), two Candida albicans and one coagulase-negative Staphylococcus (CoNS). The microbial pathogens in 11 previously healthy individuals were Streptococcus viridans (n = 3), methicillin-sensitive S. aureus (MSSA, n = 2), Haemophilus parainfluenzae (n = 2), Staphylococcus lugdunensis (n = 1), Enterococcus (n = 1), and Diphtheroid (n = 1). In total, five of 17 non-CHD patients were infected with S. aureus (two MRSA and three MSSA) and the vegetations in these five patients were detected in the right side of the heart (tricuspid valve or right atrium). The average interval between onset of symptoms and diagnosis of IE in the CHD and previously healthy groups was 18 and 31 days, respectively. Patients in the previously healthy group were older and more often required surgical interventions for removal of vegetation. CONCLUSION Over one-third (35.4%) of cases of IE in children occurred in patients without pre-existing cardiac disease. Early identification of these patients is critical and requires a high index of suspicion. The pathogenesis of IE in previously healthy individuals is still uncertain, but previous skin infection or dental problems may contribute to potential risk.

Characteristics of CTX-M Extended-Spectrum β-Lactamase-Producing Escherichia coli Strains Isolated from Multiple Rivers in Southern Taiwan

ABSTRACT Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli sequence type ST131 has emerged as the leading cause of community-acquired urinary tract infections and bacteremia worldwide. Whether environmental water is a potential reservoir of these strains remains unclear. River water samples were collected from 40 stations in southern Taiwan from February to August 2014. PCR assay and multilocus sequence typing (MLST) analysis were conducted to determine the CTX-M group and sequence type, respectively. In addition, we identified the seasonal frequency of ESBL-producing E. coli strains and their geographical relationship with runoffs from livestock and poultry farms between February and August 2014. ESBL-producing E. coli accounted for 30% of the 621 E. coli strains isolated from river water in southern Taiwan. ESBL-producing E. coli ST131 was not detected among the isolates. The most commonly detected strain was E. coli CTX-M group 9. Among the 92 isolates selected for MLST analysis, the most common ESBL-producing clonal complexes were ST10 and ST58. The proportion of ESBL-producing E. coli was significantly higher in areas with a lower river pollution index (P = 0.025) and regions with a large number of chickens being raised (P = 0.013). ESBL-producing E. coli strains were commonly isolated from river waters in southern Taiwan. The most commonly isolated ESBL-producing clonal complexes were ST10 and ST58, which were geographically related to chicken farms. ESBL-producing E. coli ST131, the major clone causing community-acquired infections in Taiwan and worldwide, was not detected in river waters.

Primary Human Immunodeficiency Virus Infection Presenting as Elevated Aminotransferases

BACKGROUND/PURPOSE Primary human immunodeficiency virus type 1 (HIV-1) infection is often under-diagnosed because of its nonspecific presentations. Elevated aminotransferase levels is one of its clinical manifestations, but is infrequently reported in the literature. The objective of this study was to investigate cases of elevated aminotransferases as a manifestation of primary HIV-1 infection. METHODS A retrospective chart review from October 1990 to May 2009 of HIV-1 infected patients in a registered database at a tertiary hospital was conducted to identify patients diagnosed with primary HIV-1 infection. An elevated aminotransferase level was broadly defined as above-normal values of alanine or aspartate aminotransferases. Acute hepatitis markers were determined using stored serum samples. RESULTS Twenty-three of the 827 (2.8%) patients were identified as having a primary HIV-1 infection. All were male, with a median age of 26 years (range, 19-77 years), and the majority were men who had sex with men (19/23, 82.6%). The most common clinical manifestations were fever (95.7%), elevated aminotransferases (65.2%), fatigue (47.8%), and pharyngitis (47.8%). The median CD4 lymphocyte count was 374/μL (range, 109-674/μL) and the median log HIV viral load was 5.0 (range, 4.3-5.9). For the 15 patients with abnormal liver function tests, the median aspartate aminotransferase level was 112 U/L (range, 62-969 U/L) and the median alanine aminotransferase level was 146 U/L (range, 42-1,110 U/L). CONCLUSION Elevated aminotransferases may be an initial manifestation of primary HIV infection and is more common than expected. Primary HIV-1 infection should be one of the differential diagnoses considered in young men presenting with unexplained, new-onset liver function impairment.

Urinary tract infection in infants caused by extended-spectrum beta-lactamase-producing Escherichia coli: comparison between urban and rural hospitals.

BackgroundCommunity-acquired urinary tract infection (UTI) caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli is an emerging problem. Compared with urban infants, rural infants may encounter different distributions of community-acquired resistant strains and various barriers to efficient management.MethodsA retrospective survey and comparison was conducted for infants with UTI caused by ESBL-producing E. coli admitted to an urban hospital (n = 111) and a rural hospital (n = 48) in southern Taiwan from 2009 to 2012.ResultsCompared with 2009 and 2010, the total number of cases at both hospitals significantly increased in 2011 and 2012 (p < 0.001). Compared with the rural patients, the urban patients were significantly younger, and they had fewer days of fever before and after admission, fewer presentations of poor activity and poor appetite, and a lower serum creatinine level. Most of the patients had no prior history of illness, and we could not identify any significant different risk factors for acquiring ESBL-producing E. coli, such as past antimicrobial use, hospitalization, UTI, and underlying renal diseases, between the urban and rural populations.ConclusionsThe increase in community-acquired UTI in infants caused by ESBL-producing E. coli was similar between the urban and rural populations. Our preliminary data suggest that the rural–urban disparities were probably related to easy access to health care by the urban population. ESBL complicates disease management, and the increase in the prevalence of ESBL producers is a major health concern and requires further healthy carrier and environmental surveillance.

Bloodstream Infection with Extended-spectrum Beta-lactamase-producing Escherichia coli: the role of virulence genes

Background Various bacterial putative virulence factors are involved in the pathogenesis of bacterial infection. However, the effect of comorbidities or infection syndrome in the association of virulence factors and mortality remains inconclusive. Method This study addressed whether specific sequence type (ST) and virulence factors of extended-spectrum beta-lactamase–producing Escherichia coli (ESBL-EC) are associated with different outcomes in patients with bloodstream infection.121 adults from southern Taiwan with ESBL-producing E. coli bloodstream infections were enrolled during a 6-year period. Demographic data, including infection syndromes, underlying disease and outcomes, were collected. The virulence factors in isolates were analyzed by PCR and multilocus sequence typing. Result Positivity for the virulence genes iha, hlyD, sat, iut, fyu, malX, ompT, usp and traT was associated with ST131 positivity (P<0.05). Some ESBL-EC virulence genes associated with urinary tract infection (UTI) were revealed. Positivity for ST405 and the virulence genes iroN and iss was significantly associated with increased 30-day mortality (death within 30 days) on univariate analysis (P<0.05). Independent risk factors of 30-day mortality in bacteremic patients with UTI included underlying chronic liver disease and malignancy. ST131 was borderline associated with 30-day mortality. Independent risk factors associated with 30-day mortality among bacteremic patients without UTI included comorbidities and iroN positivity. Conclusion In bacteremic patients with UTI, and the ST131 clone was borderline associated with mortality. Positivity for the virulence gene iroN may be linked to mortality in bacteremic patients without UTI.

Septicemia after Barium Reduction in a Pediatric Patient with Intussusception

A 4-year-old boy was admitted to our hospital because of sudden-onset abdominal pain that lasted 5 hours. He had no prior history or signs of fever, vomiting, diarrhea, or currant-jelly stools. A physical examination revealed no rebounding tenderness or palpable abdominal mass. A standing plain film of the abdomen revealed no signs of intraperitoneal free air or intestinal obstruction. Intussusception was highly suspected because of the target sign over the right upper quadrant of the abdomen on ultrasonography. A subsequent barium enema demonstrated a spring-coil appearance over the ascending colon, which was

The Clinical Outcomes of Antimicrobial Therapy in Pediatric Patients With Nontyphoid Salmonellosis With Different Levels of Severity

Background. To evaluate if a severity score could differentiate the severity of children with nontyphoid salmonellosis; clinical outcomes of antimicrobial therapy in nontyphoid salmonellosis children with different severities. Methods. Admitted children with nontyphoid salmonellosis from 1996 to 2009 were monitored. Enrolled patients were divided into no antibiotics, concordant, and discordant therapies. Besides, the patients were classified into mild, moderate, and severe group according to the severity score. Clinical outcomes were compared among them. Results. A total of 558 patients were enrolled. In no therapy subset, compared with mild group, patients had worse clinical outcomes and more complications in severe group. Patients receiving no therapy had better clinical outcomes in mild group. However, patients receiving concordant therapy (ceftriaxone) had better clinical outcomes in severe group. Conclusions. The severity score and local antibiotic susceptibility could serve as guides for antibiotic prescription for severe nontyphoid salmonellosis in children. Inappropriate antibiotic use would worsen clinical outcomes in children with mild nontyphoid salmonellosis.