Prolonged delay for controlling KPC-2-producing Klebsiella pneumoniae outbreak: the role of clinical management

BACKGROUND

Carbapenemase-producing Enterobacteriaceae (CPE) are becoming of immediate concern for infection control policies. Prompt detection of CPE on health care setting admission is crucial to halt the spread of an outbreak. We report a cluster of 13 Klebsiella pneumoniae carbapenemase (KPC)-2-producing K pneumoniae cases in a tertiary care hospital.The objective of this study was to identify contributing factors originating the outbreak.

METHODS

An outbreak investigation was conducted using descriptive epidemiology, observation of health care practices, and interviews of management staff. A root cause analysis was performed to identify patent and latent failures of infection control measures using the association of litigation and risk management method.

RESULTS

The main patent failure was the delay in identifying KPC-2-producing K pneumoniae carriers. Contributing factors were work and environmental factors: understaffing, lack of predefined protocols, staff members' characteristics, and underlying patients' characteristics. Latent failures were as follows: no promotion of the national guidelines for prevention of CPE transmission, no clear procedure for the management of patients hospitalized abroad, no clear initiative for promoting a culture of quality in the hospital, biologic activity recently outsourced to a private laboratory, and poor communication among hospital members.

CONCLUSION

Clinical management should be better promoted to control hospital outbreaks and should include team work and safety culture.

A randomized, double-blind, placebo-controlled, parallel-group, enriched-design study of nabiximols* (Sativex(®) ), as add-on therapy, in subjects with refractory spasticity caused by multiple sclerosis

BACKGROUND

  Spasticity is a disabling complication of multiple sclerosis, affecting many patients with the condition. We report the first Phase 3 placebo-controlled study of an oral antispasticity agent to use an enriched study design.

METHODS

  A 19-week follow-up, multicentre, double-blind, randomized, placebo-controlled, parallel-group study in subjects with multiple sclerosis spasticity not fully relieved with current antispasticity therapy. Subjects were treated with nabiximols, as add-on therapy, in a single-blind manner for 4weeks, after which those achieving an improvement in spasticity of ≥20% progressed to a 12-week randomized, placebo-controlled phase.

RESULTS

  Of the 572 subjects enrolled, 272 achieved a ≥20% improvement after 4weeks of single-blind treatment, and 241 were randomized. The primary end-point was the difference between treatments in the mean spasticity Numeric Rating Scale (NRS) in the randomized, controlled phase of the study. Intention-to-treat (ITT) analysis showed a highly significant difference in favour of nabiximols (P=0.0002). Secondary end-points of responder analysis, Spasm Frequency Score, Sleep Disturbance NRS Patient, Carer and Clinician Global Impression of Change were all significant in favour of nabiximols.

CONCLUSIONS

  The enriched study design provides a method of determining the efficacy and safety of nabiximols in a way that more closely reflects proposed clinical practice, by limiting exposure to those patients who are likely to benefit from it. Hence, the difference between active and placebo should be a reflection of efficacy and safety in the population intended for treatment.

Randomized study of interferon beta-1a, low-dose azathioprine, and low-dose corticosteroids in multiple sclerosis

Background

Studies evaluating interferon beta (IFNβ) for multiple sclerosis (MS) showed only partial efficacy. In many patients, IFNβ does not halt relapses or disability progression. One strategy to potentially enhance efficacy is to combine IFNβ with classical immunosuppressive agents, such as azathioprine (AZA) or corticosteroids, commonly used for other autoimmune disorders.

Objective

The Avonex–Steroids–Azathioprine study was placebo-controlled trial and evaluated efficacy of IFNβ-1a alone and combined with low-dose AZA alone or low-dose AZA and low-dose corticosteroids as initial therapy.

Methods

A total of 181 patients with relapsing–remitting MS (RRMS) were randomized to receive IFNβ-1a 30 μg intramuscularly (IM) once weekly, IFNβ-1a 30 μg IM once weekly plus AZA 50 mg orally once daily, or IFNβ-1a 30 μg IM once weekly plus AZA 50 mg orally once daily plus prednisone 10 mg orally every other day. The primary end point was annualized relapse rate (ARR) at 2 years. Patients were eligible for enrollment in a 3-year extension.

Results

At 2 years, adjusted ARR was 1.05 for IFNβ-1a, 0.91 for IFNβ-1a plus AZA, and 0.73 for combination. The cumulative probability of sustained disability progression was 16.8% for IFNβ-1a, 20.7% for IFNβ-1a plus AZA, and 17.5% for combination. There were no statistically significant differences among groups for either measure at 2 and 5 years. Percent T2 lesion volume change at 2 years was significantly lower for combination (+14.5%) versus IFNβ-1a alone (+30.3%, P < 0.05). Groups had similar safety profiles.

Conclusion

In IFNβ-naïve patients with early active RRMS, combination treatment did not show superiority over IFNβ-1a monotherapy.

Fibrinogen binding to the integrin alpha(IIb)beta(3) modulates store-mediated calcium entry in human platelets

Effects of the occupation of integrin alpha(IIb)beta(3) by fibrinogen on Ca(++) signaling in fura-2-loaded human platelets were investigated. Adding fibrinogen to washed platelet suspensions inhibited increases in cytosolic [Ca(++)] concentrations ([Ca(++)](i)) evoked by adenosine diphosphate (ADP) and thrombin in a concentration-dependent manner in the presence of external Ca(++) but not in the absence of external Ca(++) or in the presence of the nonselective cation channel blocker SKF96365, indicating selective inhibition of Ca(++) entry. Fibrinogen also inhibited store-mediated Ca(++) entry (SMCE) activated after Ca(++) store depletion using thapsigargin. The inhibitory effect of fibrinogen was reversed if fibrinogen binding to alpha(IIb)beta(3) was blocked using RDGS or abciximab and was absent in platelets from patients homozygous for Glanzmann thrombasthenia. Fibrinogen was without effect on SMCE once activated. Activation of SMCE in platelets occurs through conformational coupling between the intracellular stores and the plasma membrane and requires remodeling of the actin cytoskeleton. Fibrinogen inhibited actin polymerization evoked by ADP or thapsigargin in control cells and in cells loaded with the Ca(++) chelator dimethyl BAPTA. It also inhibited the translocation of the tyrosine kinase p60(src) to the cytoskeleton. These results indicate that the binding of fibrinogen to integrin alpha(IIb)beta(3) inhibits the activation of SMCE in platelets by a mechanism that may involve modulation of the reorganization of the actin cytoskeleton and the cytoskeletal association of p60(src). This action may be important in intrinsic negative feedback to prevent the further activation of platelets subjected.

Meloxicam, 15 mg/day, spares platelet function in healthy volunteers

OBJECTIVE

To study the influence of meloxicam, a cyclooxygenase-2 (COX-2) preferential nonsteroidal anti-inflammatory drug, on serum thromboxane and platelet function in healthy volunteers with use of the maximum recommended daily dosage of 15 mg/day.

METHODS

This study used an open, randomized crossover design. Indomethacin (INN, indometacin) was given as a positive control for nonsteroidal anti-inflammatory drug-induced inhibition of platelet function. The following variables were recorded: thromboxane B2 serum concentrations by radioimmunoassay, platelet aggregation by whole blood aggregometry in response to collagen 1.1 microg/L and to arachidonic acid 0.35 mmol/L, and closure time with use of the PFA-100.

RESULTS

Serum thromboxane B2 at baseline was 535+/-233 nmol/L (mean +/- SD) and was reduced for 95% by indomethacin to 26+/-19 nmol/L (P < .001) and for 66% by meloxicam to 183+/-62 nmol/L (P < .001). Maximal platelet aggregation in response to collagen at baseline was 18.7+/-1.6 ohms (ohms). It was reduced by indomethacin to 7.3+/-4.5 ohms (P < .001), but not by meloxicam (19+/-2.5 ohms). Platelet aggregation in response to arachidonic acid at baseline was 12.2+/-2.0 ohms. It was reduced by indomethacin in all subjects to 0 ohms, but not by meloxicam (11+/-2.4 ohms). Closure time at baseline was 128+/-24 seconds and was prolonged by indomethacin to 286+/-38 seconds (P < .001). Meloxicam caused a minor prolongation of the closure time (141+/-32 seconds; P < .05).

CONCLUSION

Meloxicam, 15 mg/day caused a major reduction of maximum thromboxane production but no reduction in collagen- or arachidonic acid-induced platelet aggregation and only minor increase of the closure time.

Acquired haemophilia A in women postpartum: management of bleeding episodes and natural history of the factor VIII inhibitor

The present study reports on the treatment of bleeding episodes and the natural history of factor VIII inhibitors in 4 patients with acquired haemophilia A postpartum. Low titre type II factor VIII inhibitors in 3 patients and high titre type I inhibitor in 1 patient became apparent immediately to 7 months after delivery. High dose human factor VIII concentrate substitution was effective in controlling bleeding episodes in two cases of factor VIII inhibitor type II, but ineffective in 1 patient with high titre type I factor VIII inhibitor. High dose gammaglobulin intravenously in 1 patient with type II factor VIII inhibitor induced a partial correction of factor VIIIc levels for 2 wk. Immunosuppressive treatment in all 4 patients with acquired haemophilia A postpartum did not reduce the potency of the factor VIII inhibitors. The low titre type II inhibitors spontaneously disappeared in all 3 patients within a few months to 1 yr after discontinuation of the immunosuppressive treatment. The high titre type I factor VIII inhibitor persisted for more than 24 yr. We conclude that immunosuppression in 4 women with acquired haemophilia A postpartum did not significantly affect the factor VIII inhibitor titre.

A specific allele of the histidine-rich glycoprotein (HRG) locus is linked with elevated plasma levels of HRG in a Dutch family with thrombosis

Recent studies describe families with both elevated plasma HRG levels and thrombosis. In order to study the possibility that allelic variants of the HRG locus are associated with differences in HRG level, we studied linkage between HRG levels and a dinucleotide repeat polymorphism in a Dutch family which was selected on the presence of both thrombosis and elevated plasma HRG levels. No other known risk factors from thrombosis were found in this family. Linkage was calculated between the dinucleotide repeat and the HRG level considering the HRG level as a quantitative phenotype assuming a population prevalence of elevated HRG of 5%. Two classes of HRG levels were defined by a mean and a variance: one class with normal HRG levels and a second class with high HRG levels. Using a mean HRG level of 99% for individuals with a normal HRG level and 145% for individuals with high HRG, a maximum lod score of 4.17 (odds in favour of linkage of 22,000:1) was found at a recombination fraction of 0, indicating linkage. Considering the pedigree, an association was found between the presence of a specific allele (no. 6) of the dinucleotide repeat polymorphism and plasma HRG levels. Family members carrying allele 6 were found to have higher HRG plasma levels compared with family members lacking allele 6 (149% v 109% respectively). We conclude that in this family, linkage is found between the HRG locus and the HRG level, and that a HRG gene coupled to allele 6 of the dinucleotide polymorphism is associated with elevated plasma HRG levels. No evidence was found for a causal relationship between elevated plasma HRG levels and thrombosis in this family.

The Nijmegen modification of the Bethesda assay for factor VIII:C inhibitors: improved specificity and reliability

Antibodies against factor VIII coagulant activity can appear in haemophiliacs who are treated with factor VIII preparations but also spontaneously in non-haemophiliacs. The Bethesda assay is the most commonly used method to detect these antibodies, but it lacks specificity especially in the lower range resulting in unreliable data. Two modifications are proposed and tested to resolve the imperfections: 1. Buffering the normal plasma used in the assay- and control mixture with 0.1 M imidazole to pH 7.4. 2. Replacing the imidazole buffer in the control mixture by immunodepleted factor VIII deficient plasma. These modifications allow better discrimination between positive and negative samples and improve reliability.

Neurological complications in children with protein C deficiency

Four children with a cerebrovascular occlusive accident and protein C deficiency are described. Two patients presented with an acute hemiplegia, the others suffered from a transient ischemic attack and a progressive hydrocephalus as the result of sinus thrombosis. In all cases protein C deficiency, Type 1, was diagnosed. Other causes of cerebrovascular disease were excluded. Although venous thrombosis has been extensively reported in protein C deficiency, these cases indicate that protein C deficiency is also related to arterial thrombosis. In evaluating children with cerebrovascular accidents, protein C deficiency should also be considered.

[Therapy of systemic mycoses in neutropenic patients using itraconazole. A comparative, randomized study with amphotericin B]

Systemic mycosis constitute a serious threat for the patient with granulocytopenia. The most important causative agents are Candida spp., Aspergillus spp. and, to a lesser extent, Cryptococcus neoformans, Mucoraceae and Pseudoallescheria boydii. Treatment of such infections with amphotericin B is difficult, because of the many side-effects of this medicine, such as hypotension, fever, shivering, thrombophlebitis, nephrotoxicity, renal tubular acidosis, hypokalaemia, anaemia and thrombocytopenia. In addition, the efficacy of amphotericin B in the treatment of proven mycotic infections in granulocytopenic patients is not very great. Itraconazole is a new, oral antifungal agent which is active in vitro and in animal experiments against both Candida and Aspergillus. In patients without granulocytopenia, itraconazole appeared to be effective in the treatment of deep Candida and Aspergillus infections. On the basis of the above data, a randomized comparative investigation was carried out unto the efficacy of amphotericin B and itraconazole in the treatment of systemic mycoses in neutropenic patients.

The efficacy of itraconazole against systemic fungal infections in neutropenic patients: a randomised comparative study with amphotericin B

In a randomised clinical trial, we compared the efficacy of the new triazole drug itraconazole (200 mg orally twice daily) with that of amphotericin B (0.6 mg/kg daily or 0.3 mg/kg in combination with flucytosine) in neutropenic (less than 500 x 10(6)/l neutrophils) patients with proven or highly suspected systemic fungal infections. Patients with unexplained fever alone were not included in the study. Of the 40 patients enrolled, 32 patients (16 males, 16 females) were evaluable. Sixteen patients (median age 49 years) were treated with itraconazole for a median period of 20 days and 16 patients (median age 32 years) received amphotericin B for a median period of 13 days. The overall clinical response was 10/16 (63%) for patients treated with itraconazole and 9/16 (56%) for patients treated with amphotericin B (P greater than 0.90). Itraconazole seemed to be more effective against Aspergillus infections, whereas amphotericin B seemed to be more effective against candidal infections, although the differences were not statistically significant.

Long-term oral ciprofloxacin for infection prophylaxis in allogeneic bone marrow transplantation

The efficacy of oral ciprofloxacin to prevent bacterial infections during the first three months after allogeneic bone marrow transplantation (BMT) was assessed prospectively. Twenty-three recipients of lymphocyte depleted marrow grafts received ciprofloxacin orally, 500 mg twice daily for 90 days after BMT. Nine patients had no infections during ciprofloxacin prophylaxis; in the remaining 14 patients 19 febrile episodes occurred. No infections could be attributed to Gram-negative rods nor to fungal micro-organisms on the basis of the micro-organisms isolated. One infection, a pneumonia due to Bacteroides melaninogenicus, proved to be fatal. Allergic skin reactions were observed in three patients, but neither hematological nor nephrological side-effects could be substantiated in patients who were treated concomitantly with cyclosporine. Prolonged administration of ciprofloxacin turned out to be safe and effective in preventing serious aerobic bacterial infections during the first three months after BMT.