Vancomycin-induced thrombocytopenia in a 60-year-old man: a case report

<p>Abstract</p> <p>Introduction</p> <p>Vancomycin, a glycopeptide antibiotic, is used to treat resistant gram-positive infections. There has been a 10- to 20-fold increase in its use over the past 25 years. Although ototoxicity and nephrotoxicity are well known side effects of vancomycin, it can also induce platelet reactive antibodies leading to life-threatening thrombocytopenia. Vancomycin is often clinically overlooked as a cause of thrombocytopenia, especially in a scenario of sepsis or when there is use of heparin. We report a proven case of vancomycin-induced thrombocytopenia and its reversal after discontinuation of vancomycin.</p> <p>Case presentation</p> <p>A 60-year-old man with a history of hypertension, congestive heart failure and dyslipidemia was admitted for a right shoulder rotator cuff tear. He underwent right-shoulder arthroscopy and rotator cuff repair. About three weeks later, he developed pain, swelling and purulent drainage from his right shoulder. Arthroscopic irrigation and drainage was then performed. Intraoperative fluid revealed the presence of <it>Methicillin susceptible Staphylococcus aureus</it>, vancomycin-sensitive <it>Enterococcus spp</it>. and <it>Serratia marcescens</it>. The patient had no known allergies. After reviewing his antimicrobial susceptibility, he was started on vancomycin 1500 mgs intravenously every 12 hours (to treat both <it>Staphylococcus aureus</it> and <it>Enterococcus spp</it>) and ciprofloxacin 750 mgs by oral induction every 12 hours. The patient's condition improved following antibiotic treatment. He was discharged and allowed to go home on IV vancomycin and oral ciprofloxacin. The patient's platelet count on the day of starting vancomycin therapy was 253 × 10³/mm³. At weeks one, two and three, the counts were 231 × 10³/mm³, 272 × 10³/mm and 6 × 103/mm³, respectively. The patient was admitted for further work-up of the thrombocytopenia. He was later shown to have vancomycin-induced platelet-reactive antibodies, causing significant thrombocytopenia, and then reversal after his vancomycin medication was discontinued.</p> <p>Conclusion</p> <p>Thrombocytopenia is a potentially life-threatening condition. Vancomycin is often clinically overlooked as a cause of thrombocytopenia, especially in a scenario of sepsis or when there is use of heparin. Simple laboratory testing with drug-dependent antibodies can be helpful in identifying vancomycin as a cause of thrombocytopenia.</p

In vitro activity of vancomycin, quinupristin/dalfopristin, and linezolid against intact and disrupted biofilms of staphylococci

Shed cells or disrupted parts of the biofilm may enter the circulation causing serious and very hard to treat biofilm-associated infections. The activity of antimicrobial agents against the shed cells/disrupted biofilms is largely unknown. METHODS: We studied the in vitro susceptibility of intact and disrupted biofilms of thirty clinical isolates of methicillin-resistant and methicillin–susceptible Staphylococcus aureus (MRSA and MSSA) and Staphylococcus epidermidis to vancomycin, quinupristin/dalfopristin, and linezolid and compared it to that of the suspended (planktonic) cells. RESULTS: Bacteria in the disrupted biofilms were as resistant as those in the intact biofilms at the minimum inhibitory concentrations of the antibiotics. At higher concentrations, bacteria in the disrupted biofilms were significantly (P < 0.001) less resistant than those in the intact biofilms but more resistant than the planktonic cells. Quinupristin/dalfopristin showed the best activity against cells of the disrupted biofilms at concentrations above MICs and vancomycin, at 500 and 1,000 μg/ml, was significantly more active against the biofilms of MRSA and S. epidermidis CONCLUSION: The difficulty of treating biofilm-associated infections may be attributed not only to the difficulty of eradicating the biofilm focus but also to the lack of susceptibility of cells disrupted from the biofilm to antimicrobial agents

Influence of TRPV1 on diabetes-induced alterations in thermal pain sensitivity

A common complication associated with diabetes is painful or painless diabetic peripheral neuropathy (DPN). The mechanisms and determinants responsible for these peripheral neuropathies are poorly understood. Using both streptozotocin (STZ)-induced and transgene-mediated murine models of type 1 diabetes (T1D), we demonstrate that Transient Receptor Potential Vanilloid 1 (TRPV1) expression varies with the neuropathic phenotype. We have found that both STZ- and transgene-mediated T1D are associated with two distinct phases of thermal pain sensitivity that parallel changes in TRPV1 as determined by paw withdrawal latency (PWL). An early phase of hyperalgesia and a late phase of hypoalgesia are evident. TRPV1-mediated whole cell currents are larger and smaller in dorsal root ganglion (DRG) neurons collected from hyperalgesic and hypoalgesic mice. Resiniferatoxin (RTX) binding, a measure of TRPV1 expression is increased and decreased in DRG and paw skin of hyperalgesic and hypoalgesic mice, respectively. Immunohistochemical labeling of spinal cord lamina I and II, dorsal root ganglion (DRG), and paw skin from hyperalgesic and hypoalgesic mice reveal increased and decreased TRPV1 expression, respectively. A role for TRPV1 in thermal DPN is further suggested by the failure of STZ treatment to influence thermal nociception in TRPV1 deficient mice. These findings demonstrate that altered TRPV1 expression and function contribute to diabetes-induced changes in thermal perception

A Case of Stenotrophomonas maltophilia Keratitis Effectively Treated with Moxifloxacin

A 70-year-old man with a long history of diabetes mellitus presented to our hospital (Department of Ophthalmology, Sahm Yook Medical Center, Seoul, Korea) complaining of severe ocular pain and visual disturbance in his left eye that had started three days prior to admission. A round 3.7 × 5.0 mm dense central stromal infiltrate with an overlying epithelial defect was noted on slit-lamp examination. Following corneal scrapings and culture, topical 0.5% moxifloxacin and 0.5% tobramycin were administered hourly. A few days later, Stenotrophomonas maltophilia was isolated in a bacterial culture from a corneal specimen. According to the results of susceptibility tests, topical 0.5% moxifloxacin was given every hour and 0.5% tobramycin was stopped. The patient's clinical features improved steadily with treatment. The corneal epithelium healed rapidly, and the infiltrate resolved within four weeks of the initiation of treatment. The patient's best corrected visual acuity improved from hand motion to 20 / 25

Bacterial and fungal microflora in surgically removed lung cancer samples

<p>Abstract</p> <p>Background</p> <p>Clinical and experimental data suggest an association between the presence of bacterial and/or fungal infection and the development of different types of cancer, independently of chemotherapy-induced leukopenia. This has also been postulated for the development of lung cancer, however the prevalence and the exact species of the bacteria and fungi implicated, have not yet been described.</p> <p>Aim</p> <p>To determine the presence of bacterial and fungal microflora in surgically extracted samples of patients with lung cancer.</p> <p>Materials and methods</p> <p>In this single-center prospective, observational study, tissue samples were surgically extracted from 32 consecutive patients with lung cancer, and reverse-transcription polymerase chain reaction (RT-PCR) was used to identify the presence of bacteria and fungi strains.</p> <p>Results</p> <p>The analysis of the electrophoresis data pointed out diversity between the samples and the strains that were identified. Mycoplasma strains were identified in all samples. Strains that appeared more often were Staphylococcus epidermidis, Streptococcus mitis and Bacillus strains, followed in descending frequency by Chlamydia, Candida, Listeria, and Haemophilus influenza. In individual patients Legionella pneumophila and Candida tropicalis were detected.</p> <p>Conclusions</p> <p>A diversity of pathogens could be identified in surgically extracted tissue samples of patients with lung cancer, with mycoplasma strains being present in all samples. These results point to an etiologic role for chronic infection in lung carcinogenesis. Confirmation of these observations and additional studies are needed to further characterize the etiologic role of inflammation in lung carcinogenesis.</p

In Vitro Evaluation of Enterococcus faecalis Adhesion on Various Endodontic Medicaments

E. faecalis in endodontic infection represents a biofilm type of disease, which explains the bacteria’s resistance to various antimicrobial compounds and the subsequent failure after endodontic treatment. The purpose of this study was to compare antimicrobial activities and bacteria kinetic adhesion in vitro for three endodontic medicaments with a clinical isolate of E. faecalis. We devised a shake culture which contained the following intracanalar preparations: CPD, Endoidrox (EIX), PulpCanalSealer (PCS); these were immersed in a liquid culture medium inoculated with the microorganism. The shake system velocity was able to prevent non-specific bacteria adhesion and simulated the salivary flow. Specimens were collected daily (from both the medium and medicaments) for 10 days; the viable cells were counted by plate count, while the adhesion index AI° [E. faecalis fg DNA] /mm2 was evaluated in the pastes after DNA extraction, by quantitative real time PCR for the 16S rRNA gene. A partial growth inhibition, during the first 24 hours, was observed in the liquid medium and on the medicaments for EIX and subsequently for CPD (six logs). EIX showed the lowest adhesion coefficient (5*102 [fg DNA]/mm2) for nine days and was similar to the control. PCS showed no antimicrobial/antibiofilm properties. This showed that “calcium oxide” base compounds could be active against biofilm progression and at least in the short term (2-4 days) on E. faecalis cells growing in planktonic cultures

Effect of a multi-faceted quality improvement intervention on inappropriate antibiotic use in children with non-bloody diarrhoea admitted to district hospitals in Kenya

BACKGROUND: There are few reports of interventions to reduce the common but irrational use of antibiotics for acute non-bloody diarrhoea amongst hospitalised children in low-income settings. We undertook a secondary analysis of data from an intervention comprising training of health workers, facilitation, supervision and face-to-face feedback, to assess whether it reduced inappropriate use of antibiotics in children with non-bloody diarrhoea and no co-morbidities requiring antibiotics, compared to a partial intervention comprising didactic training and written feedback only. This outcome was not a pre-specified end-point of the main trial. METHODS: Repeated cross-sectional survey data from a cluster-randomised controlled trial of an intervention to improve management of common childhood illnesses in Kenya were used to describe the prevalence of inappropriate antibiotic use in a 7-day period in children aged 2-59 months with acute non-bloody diarrhoea. Logistic regression models with random effects for hospital were then used to identify patient and clinician level factors associated with inappropriate antibiotic use and to assess the effect of the intervention. RESULTS: 9, 459 admission records of children were reviewed for this outcome. Of these, 4, 232 (44.7%) were diagnosed with diarrhoea, with 130 of these being bloody (dysentery) therefore requiring antibiotics. 1, 160 children had non-bloody diarrhoea and no co-morbidities requiring antibiotics-these were the focus of the analysis. 750 (64.7%) of them received antibiotics inappropriately, 313 of these being in the intervention hospitals vs. 437 in the controls. The adjusted logistic regression model showed the baseline-adjusted odds of inappropriate antibiotic prescription to children admitted to the intervention hospitals was 0.30 times that in the control hospitals (95%CI 0.09-1.02). CONCLUSION: We found some evidence that the multi-faceted, sustained intervention described in this paper led to a reduction in the inappropriate use of antibiotics in treating children with non-bloody diarrhoea. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number Register ISRCTN42996612