Israel Medical Association Journal

Abstract

During recent months, the Centers for Disease Control and Prevention (CDC) announced the occurrence of three major biosafety incidents, raising serious concern about biosafety and biosecurity guideline implementation in the most prestigious agencies in the United States: the CDC, the National Institutes of Health (NIH) and the Federal Drug Administration (FDA). These lapses included: a) the mishandling of Bacillus anthracis spores potentially exposing dozens of employees to anthrax; b) the shipment of low pathogenic influenza virus unknowingly cross-contaminated with a highly pathogenic strain; and c) an inventory lapse of hundreds of samples of biological agents, including six vials of variola virus kept in a cold storage room for decades, unnoticed. In this review we present the published data on these events, report the CDC inquiry’s main findings, and discuss the key lessons to be learnt to ensure safer scientific practice in biomedical and microbiological service and research laboratories.

Abstract

Background: Hyperhomocysteinemia is associated with increased cardiovascular risk, but treatment with folic acid has no effect on outcome in unselected patient populations.

Objectives: To confirm previous observations on the association of homozygosity for the TT MTHFR genotype with B12 deficiency and endothelial dysfunction, and to investigate whether patients with B12 deficiency should be tested for 677MTHFR genotype.

Methods: We enrolled 100 individuals with B12 deficiency, tested them for the MTHFR C677T polymorphism and measured their homocysteine levels. Forearm endothelial function was checked in 23 B12-deficient individuals (13 with TT MTHFR genotype and 10 with CT or CC genotypes). Flow-mediated dilatation (FMD) was tested after short-term treatment with B12 and folic acid in 12 TT MTHFR homozygotes.

Results: Frequency of the TT MTHFR genotype was 28/100 (28%), compared with 47/313 (15%) in a previously published cohort of individuals with normal B12 levels (P = 0.005). Mean homocysteine level was 21.2 ± 16 mM among TT homozygotes as compared to 12.3 ± 5.6 mM in individuals with the CC or CT genotype (P = 0.008). FMD was abnormal (£ 6%) in 9/13 TT individuals with B12 deficiency (69%), and was still abnormal in 7/12 of those tested 6 weeks after B12 and folic treatment (58%).

Conclusions: Among individuals with B12 deficiency, the frequency of the TT MTHFR genotype was particularly high. The TT polymorphism was associated with endothelial dysfunction even after 6 weeks of treatment with B12 and folic acid. Based on our findings we suggest that B12 deficiency should be tested for MTHFR polymorphism to identify potential vascular abnormalities and increased cardiovascular risk. 

Abstract

Background: Human herpes virus-6 (HHV-6) reactivation after hematopoietic stem cell transplantation (HSCT) is well known and has been linked with several clinical manifestations. The significance of HHV-6 viremia and related complications in this setting is still unclear.

Objective: To estimate the incidence of HHV-6 reactivation and associated morbidity in children undergoing allogeneic HSCT.

Methods: Blood samples obtained weekly (for cytomegalovirus surveillance) from children who underwent allogeneic HCST during the period January 2006–June 2010 were retrospectively tested for the presence of HHV-6 DNA using standard real-time polymerase chain reaction (PCR) assay. Clinical records were reviewed for correlation between viremia and clinical manifestations.

Results: Samples from 39 children were tested. Twenty patients had viral loads above 1000 copies/ml (51%) in at least one sample. Higher viral loads were seen in patients with primary immunodeficiency and in those with cord blood transplant. Attributable symptoms were present in 12 patients (60%) concurrently with positive PCR. Clinical manifestations spontaneously resolved without treatment in most cases, concomitantly with a decrease in viral load.

Conclusions: HHV6 reactivation during allogeneic HSCT is common. HHV-6 reactivation should be considered in patients with graft-vs-host disease-like rash, onset of CNS symptoms, delay in engraftment, and in patients after cord blood transplantation.

Abstract

Parenteral nutrition (PN) must be initiated as soon as possible after delivery in very low birth weight (VLBW) preterm infants in order to prevent postnatal growth failure and improve neurodevelopmental outcome. When administered early, high levels of parenteral amino acids (AA) are well tolerated and prevent negative nitrogen balance. Although proteins are the driving force for growth, protein synthesis is energy demanding. Intravenous lipid emulsions (ILE) constitute a good energy source because of their high energy density and provide essential fatty acids (FA) along with their long-chain polyunsaturated fatty acid (LC-PUFA) derivatives necessary for central nervous system and retinal development. Early supply of ILE is not associated with increased morbidity. No significant differences were found between ILE based on soybean oil only and mixed ILE containing soybean oil in combination with other fat sources, except for a reduction in the incidence of sepsis with non-pure soybean ILE, and possibly less PN-associated liver disease with mixed ILE containing some fish oil. In preterm infants glucose homeostasis is still immature in the first days of life and abnormalities of glucose homeostasis are common. VLBW infants may not tolerate high levels of glucose infusion without hyperglycemia. Administering lower levels of glucose infusion as part of full early PN seems more successful than insulin at this stage. Postpartum there is a transition period when the water and electrolyte balance may be severely disturbed and should be closely monitored. Avoiding fluid overload is critical for preventing respiratory and other morbidities

Abstract

Background: The mass influx of immigrants from tuberculosis-endemic countries into Israel was followed by a considerable increase in the incidence of tuberculosis (TB). All contacts of active TB patients are obliged to be screened by tuberculin skin tests (TST) and, if found positive, prophylactic treatment is considered.

Objectives: To assess the utility of interferon-gamma (IFNγ)-release assay with a prolonged follow-up in preventing unnecessary anti-TB therapy in individuals with suspected false positive results.

Methods: Between 2008 and 2012 the QuantiFERON TB gold-in-tube test (QFT-G) was performed in 278 sequential individuals who were mostly TST-positive and/or were in contact with an active TB patient. In all, whole blood was examined by the IFNγ-release assay. We correlated the TST diameter with the QFT-G assay and followed those patients with a negative assay.

Results: The QFT-G test was positive in only 72 (42%) of all 171 TST-positive individuals. There was no correlation between the diameter of TST and QFT-G positivity. Follow-up over 5 years was available in 128 (62%) of all QFT-G-negative individuals. All remained well and none developed active TB.

Conclusions: A negative QFT-G test may obviate the need for anti-TB therapy in more than half of those with a positive TST.

Abstract

Background: Iatrogenic ureteral injury may be seen following abdominopelvic surgeries. While ureteral injuries identified during surgery should be immediately and surgically repaired, those that are postoperatively diagnosed may be treated non-surgically by draining the ipsilateral kidney. Data regarding the outcome of this approach are still missing.

Objectives: To evaluate the success rates of non-surgical management of ureteral injuries diagnosed following abdominopelvic surgeries.

Methods: We retrospectively reviewed the files of all patients treated for iatrogenic ureteral injuries diagnosed following abdominopelvic surgeries. Patients' ipsilateral kidney was percutaneously drained following diagnosis of injury by either nephrostomy tube (NT)/nephro-ureteral stent (NUS) or double-J stent (DJS) inserted retrogradely. The tube was left in place until a pyelogram confirmed healing or a conservative approach was abandoned due to failure.

Results: Twenty-nine patients were identified as having ureteral injury following abdominopelvic surgery. Median time from injury to renal drainage was 9 days, interquartile range (IQR) 4–17 days. Seven cases (24%) had surgical repair. Among the other 22 patients, in 2 oncology patients the conservative approach was maintained although renal drainage failed to resolve the injury. In the remaining 20, median drainage length was 60 days (IQR 43.5–85). Calculated overall success rates following renal drainage was 69% (18/29), and with NS approached 78.5%.

Conclusions: Ureteral injuries diagnosed following abdominopelvic surgeries can be treated conservatively. Ipsilateral renal drainage should be the first line of treatment before surgical repair, and NUS may be the preferred drainage to obtain spontaneous ureteral healing. 

Abstract

Background: Diabetes mellitus-related lower extremity amputation is a major complication severely affecting patient survival and quality of life.

Objectives: To analyze epidemiological and clinical trends in the incidence and survival of lower extremity amputations among diabetes patients.

Methods: We conducted a retrospective observational cohort study of 565 consecutive diabetes patients who underwent their first non-traumatic lower extremity amputation between January 2002 and December 2009.

Results: Major amputations were performed in 316 (55.9%) patients: 142 above the knee (25.1%) and 174 below (30.8%); 249 (44.1%) had a minor amputation. The incidence rates of amputations decreased from 2.9 to 2.1 per 1000 diabetes patients. Kaplan-Meier survival analysis showed that first year mortality rates were lower among patients with minor amputations (31.7% vs. 39.6%, P = 0.569). First year mortality rates following below-knee amputation were somewhat lower than above-knee amputation (33.1 vs.45.1%, respectively). Cox regression model of survival at 1 year after the procedure found that age (HR 1.06 per year, 95% CI 1.04–1.07, P < 0.001), above-knee amputation (HR 1.36, 95% CI 1.01–1.83, P = 0.045) and ischemic heart disease (HR 1.68, 95% CI 1.26–2.24, P < 0.001) significantly increased one year mortality risk.

Conclusions: In this population-based study the incidence rate of non-traumatic amputations in diabetes patients between January 2002 and December 2009 decreased slightly. However, one year mortality rates after the surgery did not decline and remained high, stressing the need for a multidisciplinary effort to prevent amputations in diabetes patients.

Abstract

Background: Scleroderma lung disease (ILD-SSc) is treated mainly with cyclophosphamide (CYC). The effectiveness of CYC was judged after 12–24 months in most reports.

Objectives: To analyze the effect of monthly intravenous CYC on pulmonary function tests including forced vital capacity (FVC) and diffusing lung capacity (DLCO), as well as Rodnan skin score (mRSS), during long-term follow-up.

Methods: We retrospectively collected the data on 26 ILD-SSc patients who began CYC treatments before 2007. Changes in FVC, DLCO and mRSS before treatment, and at 1, 4 and 7 years after completion of at least six monthly intravenous CYC treatments for ILD-SSc were analyzed.

Results: Mean cumulative CYC dose was 8.91 ± 3.25 G. More than 30% reduction in FVC (0%, 8%, and 31% of patients), DLCO (15%, 23%, 31%), and mRSS (31%, 54%, 62%) at years 1, 4 and 7 was registered. During the years 0–4 and 4–7, annual changes in FVC, DLCO and mRSS were 3.2 vs. 0.42% (P < 0.040), 4.6 vs. 0.89% (P < 0.001), and 1.8 vs. 0.2 (P = 0.002). The greatest annual FVC and DLCO reduction over the first 4 years correlated with mortality (P = 0.022). There were no differences in the main variables regarding doses of CYC (< 6 G and > 6 G).

Conclusions: In patients with ILD-SSc, CYC stabilized the reduction of FVC during treatment, but this effect was not persistent. The vascular characteristic of ILD-SSc (DLCO) was not affected by CYC treatment. CYC rapidly improved the mRSS. This effect could be achieved with at least 6 G of CYC. Higher rates of annual reduction in FVC and DLCO in the first 4 years indicate the narrow window of opportunity and raise the question regarding ongoing immunosuppression following CYC infusions.

 

Abstract

Background: Renal hemangiomas are rare benign tumors seldom distinguished from malignant tumors preoperatively.

Objectives: To describe the Memorial Sloan-Kettering Cancer Center (MSKCC) experience with diagnosing and treating renal hemangiomas, and to explore possible clinical and radiologic features that can aid in diagnosing renal hemangiomas preoperatively.

Methods: Patients with renal hemangiomas treated at MSKCC were identified in our prospectively collected renal tumor database. Descriptive statistics were used to describe the patient characteristics and the tumor characteristics. All available preoperative imaging studies were reviewed to assess common findings and explore possible characteristics distinguishing benign hemangiomas from malignant renal tumors preoperatively.

Results: Of 6341 patients in our database 15 were identified. Eleven (73%) were males, median age at diagnosis was 53.3 years, and the affected side was evenly distributed. All but two patients were treated surgically. The mean decrease in estimated glomerular filtration rate (eGFR) after surgery was 36.3%; one patient had an abnormal presurgical eGFR and only two patients had a normal eGFR after surgery. We could not identify radiographic features that would make preoperative diagnosis certain, but we did identify features characteristic of hepatic hemangiomas that were also present in some of the renal hemangiomas.

Conclusions: Most renal hemangiomas cannot be distinguished from other common renal cortical tumors preoperatively. In select cases a renal biopsy can identify this benign lesion and the deleterious effects of extirpative surgery can be avoided.