Cerebrospinal fluid lactate and pyruvate concentrations and their ratio

ObjectivesDeterminations of cerebrospinal fluid (CSF) lactate and pyruvate concentrations and CSF lactate:pyruvate (L/P) ratios are important in several clinical settings, yet published normative data have significant limitations. We sought to determine a large dataset of stringently-defined normative data for CSF lactate and pyruvate concentrations and CSF L/P ratios.Design and methodsWe evaluated data from 627 patients who had determinations of CSF lactate and/or CSF pyruvate from 2001 to 2011 at the Cleveland Clinic. Inclusion in the normal reference population required normal CSF cell counts, glucose and protein and routine serum chemistries and absence of progressive brain disorder, epilepsy, or seizure within 24 h. Brain MRI, if done, showed no evidence of tumor, acute changes or basal ganglia abnormality. CSF cytology, CSF alanine and immunoglobulin levels, and oligoclonal band analysis were required to be normal, if done. Various inclusion/exclusion criteria were compared.Results92 patients fulfilled inclusion/exclusion criteria for a reference population. The 95% central intervals (2.5%–97.5%) for CSF lactate and pyruvate levels were 1.01–2.09 mM and 0.03–0.15 mM, respectively, and 9.05–26.37 for CSF L/P. There were no significant gender-related differences of CSF lactate or pyruvate concentrations or of CSF L/P. Weak positive correlations between the concentration of CSF lactate or pyruvate and age were noted.ConclusionsUsing stringent inclusion/exclusion criteria, we determined normative data for CSF lactate and pyruvate concentrations and CSF L/P ratios in a large, well-characterized reference population. Normalcy of routine CSF and blood analytes are the most important parameters in determining reference intervals for CSF lactate and pyruvate.     

Hypnotically induced amnesia versus ablation of memory

33 hypnotizable Ss, all capable of achieving the criterion of amnesia for a 7-digit number, were divided into 3 groups: 2 hypnotized and 1 pretend. The distributions of errors for an amnesic performance of these groups were compared with the theoretical chance distribution of errors expected in an amnesic performance. Both hypnotized groups differed signiticantly from the pretend group and from the theoretical distribution, while the performance of the pretend group did not differ significantly from the chance distribution. The performance of the pretend group conformed to the expectancy for amnesia significantly better than did the performance of either of the hypnosis groups.     

Discordance of the pediatric surgeon's intraoperative assessment of pediatric appendicitis with the pathologists report

Background/Purpose

The nature and duration of postoperative treatment in children with appendicitis is largely defined by the surgeon's intraoperative assessment of the degree of disease. Therefore, misclassification of patients could result in either inadequate or excessive duration of treatment.

Materials/Methods

During the execution of an institutional review board-approved multicenter, randomized, prospective, single-blinded trial of laparoscopic versus open appendectomy in children, we tracked the attending pediatric surgeon's determination of the degree of appendicitis and compared it to the pathologists report. Postoperative care was determined, per protocol, by the surgeon's intraoperative classification. “Interval” appendectomies were excluded from the analysis. Statistical significance was analyzed using χ² analyses.

Results

A total of 133 patients were randomized into the open group, whereas 122 randomized to laparoscopy during the first 2 years of the study. The attending pediatric surgeons and pathologists were concordant in the determination of acute appendicitis in 90% of open patients and 93% of laparoscopic patients (P = not significant). When children were classified by the attending surgeon as having complicated appendicitis (gangrenous or ruptured), the concordance rate dropped to 38% and 52%, respectively (P = not significant). When open and laparoscopic patients were combined, the length of postoperative stay (LOS) of concordantly classified acute appendicitis patients was 35 ± 16 hours. Concordantly classified complicated appendicitis LOS was 118 ± 61 hours, and discordantly classified complicated appendicitis (pathology = acute) LOS was 85 ± 41 hours (P = .01). Wound infection rates in the concordant and discordant “complicated” appendicitis groups were 23% and 7%, respectively (P = .05).When the surgeons are grouped as “junior”(n = 2) and “senior” (n = 3), there is a trend toward greater concordance in the latter group (P = .08).

Conclusions

In the 2 institutions studied, the 5 pediatric surgeon's intraoperative classification of appendicitis correlated with the pathologist's reading in a high percentage of those patients labeled “acute” but in only approximately one half of those defined as “complicated.” These phenomena are independent of the operative approach but may correlate with surgeon experience. Interventions to improve the timeliness of pathologic diagnosis may improve the accuracy and efficiency of care of pediatric appendicitis.     

Comparative performance of gated perfusion SPECT wall thickening, delayed thallium uptake, and F-18 fluorodeoxyglucose SPECT in detecting myocardial viability

To evaluate the comparative abilities of gated single photon emission computed tomography (SPECT) wall thickening, delayed thallium-201 (Tl-201) SPECT, and F-18 fluorodeoxyglucose (FDG) SPECT in detecting myocardial viability, 23 patients with previous myocardial infarction and clinically suspected viability were studied. Each patient had at least 1 extensive fixed perfusion defect on rest/stress technetium-99m sestamibi SPECT. A total of 41 major vascular territories had fixed defects. The mean (+/- 1 SD) left ventricular ejection fraction determined from gated perfusion SPECT was 26% +/- 11%. Wall thickening was assessed in a semiquantitative fashion by the regional increase in myocardial intensity during systole and was considered normal when a > or = 20% increase was observed. Tl-201 SPECT was acquired 4 hours after resting tracer injection was administered. Viability was considered present when regional defect Tl-201 count density, determined by quantitative analysis, was > 20% greater than that on the resting sestamibi scan. FDG SPECT was performed independently with a 10 mCi F-18 FDG dose after oral glucose loading was performed. A camera equipped with ultrahigh energy collimation was used. Quantitative criteria for viability were the same as for Tl-201. In the 23 patients viability within the fixed sestamibi defects was manifest by preserved wall thickening in 8 patients, delayed Tl-201 uptake in 10 patients, and FDG uptake in 18 patients. Nine major vascular territories with fixed defects were judged viable by wall thickening, 11 by Tl-201 SPECT, and 24 by FDG SPECT (P = .0009). We conclude that FDG SPECT demonstrates more evidence of myocardial viability than either gated sestamibi wall thickening or delayed Tl-201 SPECT.     

Isoniazid-related hepatic failure in children: a survey of liver transplantation centers

BACKGROUND: Isoniazid (INH) therapy for tuberculosis carries a known risk for hepatoxicity, and leads to hepatic failure in a small subset of patients. This incidence has been described for adults, but is uncertain in children. Our aim was to estimate the incidence of pediatric referrals for INH-related liver failure, and to describe the characteristics and outcomes of these patients. METHODS: The 84 U.S. centers performing pediatric liver transplants between 1987 and 1997 were surveyed regarding patients with INH-induced liver failure. Additional transplant statistics were obtained from the United Network for Organ Sharing. Estimates of the number of children taking preventive INH were derived from a nationwide public health database. RESULTS: Twenty cases of INH-related liver failure were found during a 10-year period. Four patients (20%) recovered spontaneously; 10 (50%) underwent orthotopic liver transplantation (OLT), while six (30%) died awaiting OLT. Mean age at presentation was 9.8 years (range 1.3-17). Mean length of INH therapy was 3.3 months (range 0.5-9). Notably, five patients seen for symptoms of hepatitis were initially told not to stop treatment. INH-associated liver failure accounted for 0.2% (8 of 4679) of all pediatric OLTs, and 14% (8/56) of transplants for drug hepatoxicity. The estimated incidence of liver failure was up to 3.2/100,000 for children on prophylactic INH. CONCLUSIONS: While INH-associated liver failure in children is rare, discontinuation at the onset of symptoms does not assure recovery. This indicates a need for increased awareness of hepatotoxicity risk, expanded biochemical monitoring for children receiving INH, and prompt withdrawal in symptomatic patients.     

Surgical revascularization versus endovascular therapy for chronic mesenteric ischemia: a comparative experience

INTRODUCTION: Endovascular therapy (percutaneous transluminal angioplasty [PTA] with stenting) has been increasingly applied in patients with chronic mesenteric ischemia (CMI) to avoid morbidities associated with open repair (OR). The purpose of this study was to compare outcomes of PTA/Stent vs OR in patients with symptomatic CMI. METHODS: During the interval of January 1991 to December 2005, 80 consecutive patients presenting with symptomatic CMI underwent elective revascularization. Patients with acute mesenteric ischemia or those with mesenteric revascularization performed as part of complex aneurysm repair were excluded. PTA/Stent (with stenting in 87%) was the initial procedure in 31 patients (42 vessels). OR was performed in 49 patients (88 vessels) and consisted of bypass grafting in 31 (63%), transaortic endarterectomy in 7 (14%), patch angioplasty in 4 (8%), or combined in 7 (15%). Mean follow-up was 15 months in the PTA/Stent group and 42 months in the OR cohort. Study end points included perioperative morbidity, mortality, late survival (Kaplan-Meier), and symptomatic and radiographic recurrence. RESULTS: Baseline comorbidities, with the exception of heart disease (P=.025) and serum albumin<3.5 g/dL (P=.025), were similar between PTA/Stent and OR patients. The PTA/Stent group had fewer vessels revascularized (1.5 vs 1.8 vessels, P=.001). Hospital length of stay was less for the PTA/Stent group (5.6 vs 16.7 days, P=.001). No difference was noted in in-hospital major morbidity (4/31 vs 2/49, P=.23) or mortality (1/31 vs 1/49, P=.74). Actuarial survival at 2 years was similar between the groups (88% PTA/Stent vs 74% OR, P=.28). There was no difference in the incidence of symptomatic (7/31 [23%] vs 11/49 [22%], P=.98) or radiographic recurrence (10/31 [32%] vs 18/49 [37%], P=.40) between the two groups. Radiographic primary patency (58% vs 90%, P=.001) and primary assisted patency (65% vs 96%, P<.001) at 1 year were lower in the PTA/Stent group compared with OR. Five (16%) of 31 PTA/Stent patients compared with 11 (22%) of 49 OR patients required a second intervention on at least one index vessel at any time (P=.49). CONCLUSIONS: Symptomatic recurrence requiring reintervention is common (overall 16/80 [20%]) after open and endovascular treatment for CMI. PTA/Stent was associated with decreased primary patency, primary assisted patency, and the need for earlier reintervention. In-hospital mortality or major morbidity were similar in patients undergoing PTA/Stent and OR. These findings suggest that OR and PTA/Stent should be applied selectively in CMI patients in accordance with individual patient anatomic and comorbidity considerations.     

Hyperbaric oxygen for the treatment of nonhealing arterial insufficiency ulcers

There is limited data regarding hyperbaric oxygen's effectiveness in the treatment of nonhealing arterial insufficiency ulcers. This study was designed to analyze healing rates and amputation rates in patients who underwent adjunctive hyperbaric oxygen for a nonhealing arterial insufficiency ulcer. A retrospective chart review was completed on patients who underwent hyperbaric oxygen for arterial insufficiency ulcers that failed to heal despite standard treatment. Information collected included complete ulcer healing, amputation, and patient characteristics. There were 82 patients identified. A majority did not have diabetes (84.1%). The overall rate of healing was 43.9%. The overall major amputation rate was 17.1%. The amputation rate among those who healed was 0% compared to 42.4% among those not healed (p < 0.0001). Dialysis was predictive of major amputation (p = 0.03). Our findings suggest hyperbaric oxygen can play a role in management of arterial insufficiency ulcers that have failed standard treatment. The overwhelming majority of these patients did not have diabetes, which allows this study to be translated to patients with a primary arterial insufficiency ulcer. These results support the use of hyperbaric oxygen for select nonhealing arterial insufficiency ulcers that have failed standard therapy and the need for a prospective pilot study.     

Metastatic Disease to the Clivus Mimicking Clival Chordomas

Objectives/Hypothesis A comprehensive review of the literature of clival metastases and presentation of two additional cases.Study Design Literature review and report of two cases.Methods A literature review of the MEDLINE database (1950 to January 19, 2013) was performed to identify all cases of patients with metastatic disease to the clivus. Additionally, two novel cases are presented.Results In total, 47 cases were identified in the literature, including the two cases presented in this study. Metastatic disease to the clivus is the initial presenting symptom of the primary malignancy in 36% (13/36) of the cases. When there was a history of malignancy, the median interval of time to clival metastases was 24 months (range 1 to 172 months). Clinical symptoms manifested often as cranial neuropathies, with at least abducens palsies as the initial presenting symptom in 61.9% (26/42) of patients. Tumor pathology was diverse, but several pathologies were seen more commonly: prostate carcinoma (18.1%, 9/47), hepatocellular carcinoma (10.6%, 5/47), and thyroid follicular carcinoma (8.5%, 4/47).Conclusion Although clival metastases are extremely rare, they are an important part of the differential of clival masses as they can be the presenting symptom of distant malignancy.Level of Evidence 4.