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Calvin M Kunin

Publications and source records attributed to Calvin M Kunin.

12 recordsLinked to original sources
PubMed2006

Urinary-catheter-associated infections in the elderly.

The indwelling urinary catheter is the leading cause of complicated urinary tract infections and Gram-negative bacteraemia in this age group. It accounts for about 40% of life-threatening septicaemia. There is a progressive increase in mortality independently associated with the duration of catheterization. Polymicrobial bacteriuria is common. Urease-producing bacteria lead to encrusted and blocked catheters. The current challenges are to develop effective methods to sensitize healthcare workers to avoid the routine use of indwelling catheters, remove them when no longer needed, develop alternative methods for care of incontinence, employ non-invasive methods to measure urine output, and improve urine drainage systems. The research paradigm needs to focus on prevention of catheter-associated infections rather than on futile attempts to treat irreversible sepsis.

Aged↗
PubMed2005

Trends in fluoroquinolone resistance of Mycobacterium tuberculosis complex in a Taiwanese medical centre: 1995-2003.

OBJECTIVES: Fluoroquinolones are being used more frequently for the treatment of multidrug-resistant (MDR) strains of Mycobacterium tuberculosis complex (MTB). This study was designed to determine the frequency of the emergence of fluoroquinolone-resistant strains in Taiwan and to assess whether this might be due to use of fluoroquinolones for treatment of patients with MDR or because of increased use of fluoroquinolones in the community for treatment of other infections. We also sought to determine whether there might be clonal spread of fluoroquinolone resistance. METHODS: A total of 3497 clinical isolates of M. tuberculosis complex were obtained during 1995-2003, of which 141 were selected. They consisted of 62 isolates fully susceptible to four first-line drugs, 33 isolates resistant to rifampicin and isoniazid (MDR), and 46 isolates with a variety of any drug resistant patterns other than MDR (combination group). The MICs were determined for ciprofloxacin, ofloxacin and levofloxacin. RESULTS: An increase in the MIC90 and rates of resistance to ciprofloxacin, ofloxacin and levofloxacin were noted only in the MDR group. The rates were higher among strains isolated between 1998-2003 compared with those obtained between 1995-1997 (rate of resistance, 20% versus 7.7%; MIC > or = 4 mg/L versus 1-2 mg/L). Among the 10 fluoroquinolone-resistant isolates, five (50%) possessed mutations other than S95T in the gyrA gene. No gyrB mutation was found in any of the clinical isolates. CONCLUSIONS: These findings suggest that fluoroquinolone resistance is the result of treatment of patients with MDR strains rather than from use in the general community in Taiwan. The emergence of fluoroquinolone resistance among MDR strains reinforces the need for routine fluoroquinolone susceptibility testing whenever these drugs might be used.

Amino Acid Substitution↗
PubMed2005

Who are you--Staphylococcus saprophyticus?

Staphylococcus saprophyticus is a leading cause of cystitis in young women. S. saprophyticus shares many clinical features of urinary tract infection caused by Escherichia coli, but differs in pathogenesis, seasonal variation, and geographic distribution. This review summarizes what is known and what still needs to be learned about this microorganism.

Cystitis↗
PubMed2004

Catheter-associated urinary tract infections in intensive care units can be reduced by prompting physicians to remove unnecessary catheters.

OBJECTIVE: Indwelling urinary catheters are the most common source of infections in intensive care units (ICUs). The aim of this study was to evaluate the efficacy of nurse-generated daily reminders to physicians to remove unnecessary urinary catheters 5 days after insertion. DESIGN: A time-sequence nonrandomized intervention study. SETTING: Adult ICUs (medical, surgical, cardiovascular surgical, neurosurgical, and coronary care) of a tertiary-care university medical center. PATIENTS: All patients admitted to the adult ICUs during a 2-year period. The study consisted of a 12-month observational phase (15,960 patient-days) followed by a 12-month intervention phase (15,525 patient-days). INTERVENTION: Daily reminders to physicians from the nursing staff to remove unnecessary urinary catheters 5 days after insertion. RESULTS: The duration of urinary catheterization was significantly reduced during the intervention phase (from 7.0 + 1.1 days to 4.6 +/- 0.7 days; P < .001). The rate of catheter-associated urinary tract infection (CAUTI) was also significantly reduced (from 11.5 +/- 3.1 to 8.3 +/- 2.5 patients with CAUTI per 1,000 catheter-days; P = .009). There was a linear relationship between the monthly average duration of catheterization and the rate of CAUTI (r = 0.50; P = .01). The excess monthly cost of antibiotics for CAUTI was reduced by 69% (from 4021 dollars +/- 1800 dollars to 1220 dollars +/- 941 dollars; P = .004). CONCLUSION: This study demonstrated that a simple measure instituted as part of a continuous quality improvement program significantly reduced the duration of urinary catheterization, rate of CAUTI, and additional costs of antibiotics to manage CAUTI.

Aged↗
PubMed2003

Eosinophilic meningitis caused by Angiostrongylus cantonensis associated with eating raw snails: correlation of brain magnetic resonance imaging scans with clinical findings.

Angiostrongylus cantonensis is the most common cause of eosinophilic meningitis worldwide. Human infection occurs after ingestion of the worms in raw snails or fish that serve as intermediate hosts. Two outbreaks of central nervous system infection with A. cantonensis occurred in Kaoshiung, Taiwan, during 1998 and 1999 among Thai laborers who ate raw snails. A detailed clinical studies of 17 of these patients was conducted, including study of 13 patients who underwent magnetic resonance imaging (MRI) scans of the brain. The MRI scans revealed high signal intensities over the globus pallidus and cerebral peduncle on T1-weighted imaging, leptomeningeal enhancement, ventriculomegaly, and punctate areas of abnormal enhancement within the cerebral and cerebellar hemisphere on gadolinium-enhancing T1 imaging, and a hyperintense signal on T2-weighted images. There was a significant correlation between severity of headache, cerebrospinal fluid (CSF) pleocytosis, and CSF and blood eosinophilia with MRI signal intensity in T1-weighted imaging (P < 0.05). Eosinophilic meningitis produced by A. cantonensis needs to added to the list of causes of hyperintense basal ganglia lesions found on T1-weighted MRI scans in tropical countries.

Adult↗
PubMed2002

Mefloquine and new related compounds target the F(0) complex of the F(0)F(1) H(+)-ATPase of Streptococcus pneumoniae.

The activities of mefloquine (MFL) and related compounds against previously characterized Streptococcus pneumoniae strains carrying defined amino acid substitutions in the c subunit of the F(0)F(1) H(+)-ATPase were studied. In addition, a series of MFL-resistant (Mfl(r)) strains were isolated and characterized. A good correlation was observed between inhibition of growth and inhibition of the membrane-associated F(0)F(1) H(+)-ATPase activity. MFL was about 10-fold more active than optochin and about 200-fold more active than quinine in inhibiting both the growth and the ATPase activities of laboratory pneumococcal strain R6. Mutant strains were inhibited by the different compounds to different degrees, depending on their specific mutations in the c subunit. The resistant strains studied had point mutations that changed amino acid residues in either the c subunit or the a subunit of the F(0) complex. Changes in the c subunit were located in one of the two transmembrane alpha helices: residues M13, G14, G20, M23, and N24 of helix 1 and residues M44, G47, V48, A49, and V57 of helix 2. Changes in the a subunit were also found in either of the transmembrane alpha helices, helix 5 or 6: residue L186 of helix 5 and residues W206, F209, and S214 of helix 6. These results suggest that the transmembrane helices of the c and a subunits interact and that the mutated residues are important for the structure of the F(0) complex and proton translocation.

Amino Acid Sequence↗
PubMed2002

The antimicrobial defense mechanism of the female urethra: a reassessment.

PURPOSE: This review of the literature and study of the cytology of the urethra were done to define the potential role of the female urethra as a staging site for urinary tract infection and examine the evidence for a urethral defense mechanism. MATERIALS AND METHODS: We re-analyzed data on the quantitative microbiology of the female urethra published 3 decades ago, reviewed the literature on the initiation of ascending urinary tract infections, the cytology and anatomy of the urethra, and performed studies of the morphology of urethral cells in boys and girls, men, menstruating and menopausal women, and women with acute cystitis. We also considered clues about the urethral microenvironment provided by gonococcal cervicitis and urethritis. RESULTS: We found strong statistical evidence that the female urethra has a powerful antimicrobial defense mechanism, which appears to differ in women with and without recurrent urinary tract infections. We corroborated the findings of previous investigators that the female urethra is lined by cells identical to those of the vagina that respond similarly to estrogens. We found immature basal and parabasal cells in children, and a modest inflammatory response to urinary tract infection. CONCLUSIONS: The female urethra may provide a favorable environment for colonization by uropathogens but it is protected by a powerful defense mechanism. This mechanism may be explained by the shedding of uropathogens bound to exfoliating urethral cells, trapping of bacteria by mucus secreted by the paraurethral glands, intermittent washout by urine, local production of Ig, cytokines and defensins and mobilization of leukocytes.

Adult↗
PubMed2002

Excessive use of antibiotics in the community associated with delayed admission and masked diagnosis of infectious diseases.

Resistance to antimicrobial drugs is becoming more serious throughout the world, and is a major problem in Taiwan. The selective pressure of antibiotic use makes some degree of antibiotic resistance inevitable, but extraordinarily high rates of resistance suggest excessive use. This report reviews collaborative studies undertaken in the southern city of Kaohsiung to better define the use of antibiotics in the community and to determine whether recent use of antibiotics results in delayed admission and missed or masked diagnoses of infectious diseases among patients presented at an emergency department. Because of the unreliability in the patients' medical history, antibiotic activity was determined in the urine. These studies demonstrated that (1) detection of antibiotics in the urine offers a simple and inexpensive means to determine antibiotic use when a history of drug use is unreliable; (2) the high frequency of antibiotics use among patients presenting at emergency departments, clinics, and in the community may account for the extraordinarily high rates of antimicrobial drug resistance in Taiwan; and (3) recent use of antimicrobial drugs before visiting an emergency department was associated with a significantly increased risk of delayed and masked or missed diagnoses of infectious diseases, and missed diagnosis of noninfectious diseases. These findings reflect inherent social, economic, and cultural problems and constraints in the medical care system in Taiwan. The issue of inappropriate use of antibiotics in the community, hospitals, and agriculture is now being addressed at a national level.

Adult↗
PubMed2002

Use of prophylactic antibiotics in surgery at a medical center in southern Taiwan.

BACKGROUND AND PURPOSE: Use of prophylactic antibiotics to prevent postoperative infection (POI) is a common practice in surgery. This study investigated the amount and cost of surgical prophylaxis in a representative general hospital in Taiwan in order to determine an appropriate course of action to control antibiotic use and decrease the burden of resistance. METHODS: The use of antibiotic prophylaxis for a wide variety of surgical procedures over a 6-month period was retrospectively evaluated in 3,104 patients at a medical center in southern Taiwan. RESULTS: Timing of perioperative parenteral antibiotics was inappropriate in 738 (23.8%) patients. The average duration of antibiotic use was 6.4 days (2.4 days intravenous + 4.0 days oral). Only 4.9% of patients did not receive prophylactic antibiotics and only 9.2% received a single dose. Prophylaxis exceeded 1 day in 80% of patients and 3 days in 68.2%. The most common regimen was cefazolin plus gentamicin, used in 2,338 (75.3%) procedures. There were 146 POIs in 119 (3.8%) patients. The most common POI was at the surgical site. Aerobic gram-negative bacilli were most common among the 81 pathogens isolated (54.3%), followed by gram-positive cocci (34.6%), anaerobes (8.6%) and yeasts (2.4%). The total cost for prophylactic antibiotics was New Taiwan (NT)$5,860,242 (approximately US$ 169,862). Had a single dose of cefazolin been used for all patients, the cost would have been reduced by 92.1%. Had four doses of cefazolin been used, the cost would have been reduced by 68.5%. CONCLUSIONS: This study documented the excessive use and often inappropriate timing of administration of antibiotics for surgical prophylaxis in a representative medical center in Taiwan. Strategies are needed to improve the appropriate use of surgical antibiotic prophylaxis in Taiwan, not only to reduce costs but, more importantly, to delay the emergence of resistant microorganisms.

Antibiotic Prophylaxis↗