Nerve Conduction Study Findings Research Articles

G.P.292: Nerve ultrasonography and neurophysiological study in amyotrophic lateral sclerosis to assess distal motor dysfunction of median nerve

In some patients with early stage of amyotrophic lateral sclerosis (ALS), distal motor latency (DL) prolongation without reductions of compound muscle action potential (CMAP) amplitude and motor conduction velocity (MCV) in median nerve is detected by nerve conduction study (NCS). It cannot be explained by axonal loss, and might be primary, specific lesion as the very early sign of ALS. Carpal tunnel syndrome may be complicated with ALS, or other disorders associated with ALS may occur. The aim of our study was to evaluate this pathogenesis generally by using NCS and nerve ultrasonography. Three individuals with ALS and 4 with CTS were examined nerve ultrasonography to measure the cross-sectional area (CSA) of their median nerve at wrist. NCS was also studied and we recorded DL, CMAP amplitude, sensory nerve action potential (SNAP) amplitude and sensory conduction velocity of median nerve at wrist in the patients of both groups. We compared the ALS group with the CTS group about these parameters. As for ultrasonography, no apparent abnormal findings were found in 2 CTS patients, and in other 2 CTS patients, median nerves were compressed at carpus part and enlarged at proximal to carpal tunnel. Though these findings were not found in all ALS patients, the CSA of the median nerve was smaller in the ALS patients than in the CTS patients. On the other hand, DL was prolonged in all ALS patients, CMAP amplitude was reduced in 2 out of 3 ALS patients. In 2 CTS patients, prolonged DL was found. One showed reduction of both CMAP and SNAP amplitude and the other showed only CMAP amplitude reduction. In other 2 CTS patients, NCS findings were normal. Nerve ultrasonography may demonstrates nerve atrophy in ALS even if NCS reveals similar findings to CTS and might contribute to the diagnosis of ALS in early stage.

Guillain –Barrè Syndrome following Hepatitis E

Guillain- Barrè Syndrome is characterized by acute progressive symmetric limb weakness and areflexia. A 32 year old female presented with progressive ascending areflexic muscular weakness and bilateral lower motor neuron type of facial palsy. She had anorexia, nausea and upper abdominal pain for 2 weeks. The findings of motor nerve conduction study are consistent with acute inflammatory demyelinating polyradiculoneuropathy. She had elevated liver enzyme and positive immunoglobulin M antibody against hepatitis E in blood. Based on clinical features, laboratory findings and electrophysiological study, she was diagnosed as Guillain- Barrè Syndrome following hepatitis E. She was treated with intravenous immunoglobulin and recovered fully. DOI: http://dx.doi.org/10.3329/bccj.v2i1.19973 Bangladesh Crit Care J March 2014; 2 (1): 48-49

Hypovitaminosis D in widespread pain: its effect on pain perception, quality of life and nerve conduction studies.

The aim of the study was to investigate the effects of hypovitaminosis D on pain, quality of life (QoL) and nerve conduction studies (NCSs) in patients with chronic widespread pain (CWP). We randomly selected 83 female patients with CWP according to their vitamin D levels in this cross-sectional study. Patients were divided into two groups as sufficient vitamin D level (above 20 ng/ml) and deficient vitamin D level (below 20 ng/ml, hypovitaminosis D). Various pain scales and Nottingham Health Profile (NHP) were used. NCSs were also done. In patients with hypovitaminosis D, there were significantly higher pain scores for all scales (p value range 0.002-0.027). The subscale and total NHP scores were significantly higher in hypovitaminosis D group (p = 0.048-0.001) except social isolation subscale (p = 0.553). Vitamin D levels were in negative correlation with right and left median and/or ulnar motor nerve amplitudes, left tibial motor amplitude. This study confirm that hypovitaminosis D is related with higher pain intensity and lower QoL scores in patients with CWP when compared with control group. Additionally, we identified for the first time that there were negative correlations between vitamin D levels and some findings of NCSs.

Long-term renal and neurologic outcomes among survivors of diethylene glycol poisoning.

At least 13 medication-associated diethylene glycol (DEG) mass poisonings have occurred since 1937. To our knowledge, this is the first longitudinal study characterizing long-term health outcomes among survivors beyond the acute poisoning period. To characterize renal and neurologic outcomes among survivors of a 2006 DEG mass-poisoning event in Panama for 2 years after exposure. This prospective longitudinal study used descriptive statistics and mixed-effects repeated-measures analysis to evaluate DEG-poisoned survivors at 4 consecutive 6-month intervals (0, 6, 12, and 18 months). Case patients included outbreak survivors with a history of (1) ingestion of DEG-contaminated medication, (2) hospitalization for DEG poisoning, and (3) an unexplained serum creatinine level of 1.5 mg/dL or higher (to convert to micromoles per liter, multiply by 88.4) during acute illness or unexplained exacerbation of preexisting end-stage renal disease. Demographics, mortality, dialysis dependence, renal function, neurologic signs and symptoms, and nerve conduction studies. Of the 32 patients enrolled, 5 (15.6%) died and 1 was lost to follow-up, leaving 26 patients at 18 months. Three (9.4%) missed 1 or more evaluations. The median age was 62 years (range, 15-88 years), and 59.4% were female. Three (9.4%) patients had preexisting renal failure. Enrollment evaluations occurred at a median of 108 days (range, 65-154 days) after acute illness. The median serum creatinine level for the 22 patients who were not dialysis dependent at time 0 was 5.9 mg/dL (range, 1.8-17.1 mg/dL) during acute illness and 1.8 mg/dL (range, 0.9-5.9 mg/dL) at time 0. Among non-dialysis-dependent patients, there were no significant differences in the log of serum creatinine or estimated glomerular filtration rate over time. The number of patients with subjective generalized weakness declined significantly over time (P < .001). A similar finding was observed for any sensory loss (P = .05). The most common deficits at enrollment were bilateral lower extremity numbness in 13 patients (40.6%) and peripheral facial nerve motor deficits in 7 (21.9%). All patients with neurologic deficits at enrollment demonstrated improvement in motor function over time. Among 28 patients (90.3%) with abnormal nerve conduction study findings at enrollment, 10 (35.7%) had motor axonal involvement, the most common primary abnormality. Neurologic findings of survivors tended to improve over time. Renal function generally improved among non-dialysis-dependent patients between acute illness and the first evaluation with little variability thereafter. No evidence of delayed-onset neurologic or renal disease was observed.

Age delays the recovery of distal motor latency after carpal tunnel syndrome surgery

Studies have shown slow healing of peripheral nerve injury in elderly patients. Carpal tunnel syndrome (CTS) is the most frequent compressive mononeuropathy, affecting mostly older people and females. Few studies have assessed electrophysiological differences between younger and older patients. We aimed to evaluate age-dependent differences in electrophysiological parameters preoperatively and postoperatively over a 100-day postoperative period. This retrospective study included 258 hands of patients who underwent conventional open-technique carpal tunnel syndrome surgery. Patients with paresthesia in the median nerve distribution or with impaired sensation or abnormal findings in sensory and motor median nerve conduction studies were enrolled. The age dependence of the preoperative values of distal motor latency, amplitude of the compound motor action potential and sensory conduction velocity was estimated using regression analysis. Statistically significant age dependence was found for the preoperative distal motor latency, compound motor action potential, amplitude and sensory conduction velocity. The repair of segmental demyelination was nearly twice as slow in the older group, at a 5 % significance level, even when comparing groups with the same preoperative distal motor latency. Analysis of preoperative nerve conduction parameters indicates that surgery for carpal tunnel syndrome is performed later in older patients.

Clinical, neurophysiological, and skin biopsy findings in peripheral neuropathy associated with hepatitis C virus-related cryoglobulinemia

Hepatitis C virus (HCV)-related cryoglobulinemia commonly causes disabling complications including peripheral neuropathy and neuropathic pain. In this prospective clinical, neurophysiological, and skin biopsy study we aimed at assessing clinical characteristics and risk factors of peripheral neuropathy and neuropathic pain in patients with HCV-related cryoglobulinemia. We enrolled 69 consecutive patients with HCV-related cryoglobulinemia. We diagnosed neuropathic pain with the DN4 (Neuropathic Pain Diagnostic) questionnaire, and rated the various neuropathic pains with the Neuropathic Pain Symptom Inventory (NPSI). All patients underwent a standard nerve conduction study to assess Aβ-fiber function, laser-evoked potentials to assess Aδ-fiber function, and skin biopsy to assess C-fiber terminals. Of the 69 patients studied, 47 had a peripheral neuropathy, and 29 had neuropathic pain. Patients with peripheral neuropathy were older than those without (P < 0.0001). While peripheral neuropathy was significantly associated with the duration of HCV infection (P < 0.01), it was unrelated to the duration of cryoglobulinemia and cryocrit (P > 0.5). The severity of peripheral neuropathy significantly correlated with the duration of HCV infection (P < 0.05). Laser-evoked potential amplitudes were significantly lower in patients with than in those without neuropathic pain (P < 0.05). Conversely, no difference was found in nerve conduction study and skin biopsy findings (P > 0.05). Our findings show that peripheral neuropathy is related to age and HCV infection, rather than to cryoglobulinemia, and neuropathic pain is associated with damage to nociceptive pathways as assessed with laser-evoked potentials; this might be useful for designing more effective clinical interventions for these common HCV related-cryoglobulinemia complications.

The Role of Insulin Resistance in Diabetic Neuropathy in Koreans with Type 2 Diabetes Mellitus: A 6-Year Follow-Up Study

PurposeWe previously reported that insulin resistance, low high-density lipoprotein (HDL) cholesterol, and glycaemic exposure Index are independently associated with peripheral neuropathy in Korean patients with type 2 diabetes mellitus. We followed the patients who participated in that study in 2006 for another 6 years to determine the relationship between insulin resistance and neuropathy.Materials and MethodsThis study involved 48 of the original 86 Korean patients with type 2 diabetes mellitus who were referred to the Neurology clinic for the assessment of diabetic neuropathy from January 2006 to December 2006. These 48 patients received management for glycaemic control and prevention of diabetic complications in the outpatient clinic up to 2012. We reviewed blood test results and the nerve conduction study findings of these patients, taken over a 6-year period.ResultsLow HDL cholesterol and high triglycerides significantly influenced the development of diabetic neuropathy. Kitt value (1/insulin resistance) in the previous study affected the occurrence of neuropathy, despite adequate glycaemic control with HbA1c <7%. Insulin resistance affected the development of diabetic neuropathy after 6 years: insulin resistance in 2006 showed a positive correlation with a change in sural sensory nerve action potential in 2012.ConclusionDiabetic neuropathy can be affected by previous insulin resistance despite regular glycaemic control. Dyslipidaemia should be controlled in patients who show high insulin resistance because HDL cholesterol and triglycerides are strongly correlated with later development of diabetic neuropathy.

Reversible conduction failure in overlap of Miller Fisher syndrome and pharyngeal–cervical–brachial variant of Guillain-Barré syndrome in the spectrum of nodo-paranodopathies

Patients with an overlap of the pharyngeal–cervical–brachial variant of Guillain–Barré syndrome and Miller Fisher syndrome (PCB/MFS) have rarely been reported. The electrophysiological findings in PCB/MFS are of great interest and may provide insight into the pathophysiology of the disorder. We report the clinical features and nerve conduction study findings in a patient with PCB/MFS with high titers of antiganglioside antibodies against GQ1b, GD1a, and GD1b. In serial nerve conduction studies, compound muscle action potential amplitudes normalised without development of temporal dispersion within 3weeks, and absent median, ulnar, and sural sensory nerve action potentials became recordable within 4months. These findings are consistent with reversible conduction failure in both motor and sensory fibres, and PCB/MFS could be classified in the recently described nodo-paranodopathy spectrum of acute neuropathies associated with anti-ganglioside antibodies.

Diagnosis From Functional Perspectives: Usefulness of a Manual Tactile Test for Predicting Precision Pinch Performance and Disease Severity in Subjects With Carpal Tunnel Syndrome

ObjectivesTo investigate how the severity levels revealed in a nerve conduction study (NCS) affect the results of the Manual Tactile Test (MTT) for patients with carpal tunnel syndrome (CTS), and to examine the relationships between the results of the MTT and precision pinch performance. DesignCase-control studies. SettingHospital and local community. ParticipantsPatients with CTS (N=70) with 119 affected hands were studied. A control group matched by age, sex, and hand dominance was also recruited. InterventionNot applicable. Main Outcome MeasuresCTS severity was determined based on NCS findings. The MTT, traditional sensory tests, and precision pinch performance were used to examine the functional sensory status of the hand from different perspectives. ResultsThe patients with CTS exhibited deterioration in all of the sensibility tests (P<.001). The results showed that the MTT could classify subgroups of severity in CTS (P<.001). A moderate correlation was found between the results of the MTT and precision pinch performance (r=.526–.585, P<.001). Multiple linear regression analysis showed that the MTT results were useful indicators for predicting precision pinch performance and differentiating severity in subjects with CTS (r2=.376 and .323, respectively). ConclusionsThe findings indicate that the MTT could be a valid and useful assessment for hand sensibility and prehensile pinch performance in patients with CTS.

Which nerve conduction parameters can predict spontaneous electromyographic activity in carpal tunnel syndrome?

ObjectiveWe investigate electrodiagnostic markers to determine which parameters are the best predictors of spontaneous electromyographic (EMG) activity in carpal tunnel syndrome (CTS). MethodsWe enrolled 229 patients with clinically proven and nerve conduction study (NCS)-proven CTS, as well as 100 normal control subjects. All subjects were evaluated using electrodiagnostic techniques, including median distal sensory latencies (DSLs), sensory nerve action potentials (SNAPs), distal motor latencies (DMLs), compound muscle action potentials (CMAPs), forearm median nerve conduction velocities (FMCVs) and wrist–palm motor conduction velocities (W–P MCVs). All CTS patients underwent EMG examination of the abductor pollicis brevis (APB) muscle, and the presence or absence of spontaneous EMG activities was recorded. Normal limits were determined by calculating the means±2 standard deviations from the control data. Associations between parameters from the NCS and EMG findings were investigated. ResultsIn patients with clinically diagnosed CTS, abnormal median CMAP amplitudes were the best predictors of spontaneous activity during EMG examination (p<0.001; OR 36.58; 95% CI 15.85–84.43). If the median CMAP amplitude was ⩽2.1mV, the rate of occurrence of spontaneous EMG activity was >95% (positive predictive rate >95%). If the median CMAP amplitude was higher than the normal limit (>4.9mV), the rate of no spontaneous EMG activity was >94% (negative predictive rate >94%). An abnormal SNAP amplitude was the second best predictor of spontaneous EMG activity (p<0.001; OR 4.13; 95% CI 2.16–7.90), and an abnormal FMCV was the third best predictor (p=0.01; OR 2.10; 95% CI 1.20–3.67). No other nerve conduction parameters had significant power to predict spontaneous activity upon EMG examination. ConclusionsThe CMAP amplitudes of the APB are the most powerful predictors of the occurrence of spontaneous EMG activity. Low CMAP amplitudes are strongly associated with spontaneous activity, whereas high CMAP amplitude are less associated with spontaneous activity, implying that needle EMG examination should be recommended for the detection of spontaneous activity in those CTS patients whose NCS reveals CMAP amplitudes between 2.1mV and the lower normal limit (4.9mV in the present study). SignificanceUsing NCS, electromyographers can predict the presence of spontaneous EMG activity in CTS patients.

Sonographic and electrophysiologic findings in patients with meralgia paresthetica

ObjectiveThis study was aimed to demonstrate the usefulness of ultrasonography in the diagnosis of meralgia paresthetica (MP). MethodsClinical data, sensory nerve conduction study and sonographic findings of 23 patients with unilateral MP were analyzed retrospectively. Twelve healthy subjects were recruited for the optimal cut-off value for the cross-sectional area of LFCN to diagnose MP using receiver operating characteristic curves. ResultsThe median value of the cross-sectional area of LFCN in healthy subjects was 3mm2 and in the affected and unaffected sides in patients with MP, they were 11 and 6.5mm2 around the anterior superior iliac spine level. The optimal cut-off value for the diagnosis of MP was 5mm2. The location of LFCN on the affected side was superior to the inguinal ligament in 12 out of 23 cases (50%). ConclusionUltrasonography is useful in the diagnosis of MP as a supplemental diagnostic tool, which gives important information about the morphologic changes that occur in the LFCN and its course. SignificanceTo the best of our knowledge, this is the first report to suggest that describe the cutoff value of the cross-sectional area of LFCN for the diagnosis of MP using ultrasonography.

早期の多剤併用療法導入が有効であったHIV関連慢性炎症性脱髄性多発根神経炎の1例

A 47-year-old man with HIV infection presented with lower leg dominant dysesthesia, muscle weakness and sensory ataxia of 3 month's duration. Nerve conduction studies (NCS) showed demyelination change in the median and tibial nerves and sensory nerve action potential (SNAP) in the sural nerve was not evoked. Somatosensory evoked potential (SEP) showed the delayed N9 latency. Diagnose of HIV-associated chronic inflammatory demyelinating polyneuropathy (CIDP) was made. Although the CD4 lymphocyte counts were relatively preserved (466/μl), highly active anti-retroviral therapy (HAART) was started according to a new guideline for the use of antiretroviral agents in HIV-1-infected adults and adolescents recommending early initiation of treatment. After six months, HIV1-RNA was not detected and the CD4 lymphocyte counts showed a recovering trend (585/μl). His symptoms had disappeared, except for dysesthesia in the tip of a toe. Repeated NCS demonstrated full recovery from the demyelination and appearance of SNAP in the sural nerve. The improvement of his symptoms and NCS findings has been maintained for two years. Although effectiveness of immunotherapies such as oral prednisone, high-dose immunoglobulins and plasmapheresis have been reported in HIV-associated CIDP, early initiation of HAART may be also important for favorable prognosis in HIV-associated CIDP.

A Case of Acute Motor and Sensory Axonal Neuropathy Following Hepatitis A Infection

Acute motor and sensory axonal neuropathy (AMSAN) are recently described subtypes of Guillain-Barre syndrome characterized by acute onset of distal weakness, loss of deep tendon reflexes, and sensory symptoms. A 21-yr-old male was transferred to our hospital due to respiration difficulties and progressive weakness. In laboratory findings, immunoglobulin M antibodies against hepatitis A were detected in blood and cerebrospinal fluid. The findings of motor nerve conduction studies showed markedly reduced amplitudes of compound muscle action potentials in bilateral peroneal, and posterior tibial nerves, without evidence of demyelination. Based on clinical features, laboratory findings, and electrophysiologic investigation, the patient was diagnosed the AMSAN following acute hepatitis A viral infection. The patient was treated with intravenous immunoglobulin and recovered slowly. Clinicians should consider this rare but a serious case of AMSAN following acute hepatitis A infection.

Abnormal nerve conduction study findings indicating the existence of peripheral neuropathy in multiple sclerosis and neuromyelitis optica.

Objective. Chronic inflammatory demyelinating polyneuropathy (CIDP) has been reported in patients with multiple sclerosis (MS). However, there have been limited reports of peripheral neuropathy as a complication of neuromyelitis optica (NMO). In this paper, we showed the characteristics and differences between peripheral neuropathy as a complication of MS and NMO. Method. We analyzed a series of 58 MS and 28 NMO patients and evaluated nerve conduction studies (NCS) in 21 MS and 5 NMO patients. Results. Six of the 58 MS and 3 of the 28 NMO patients revealed abnormal NCS findings. Three (5.2%) of the 58 MS patients fulfilled the criteria for CIDP. One (3.6%) of the 28 NMO patients showed peripheral neuropathy at the same time of NMO relapse, although CIDP was not seen in NMO. The other 5 (3 MS and 2 NMO) patients were complicated with neuropathy caused by concomitant diabetes mellitus and Sjögren's syndrome. Conclusion. Frequency of abnormal NCS findings might exhibit no significant difference between MS and NMO, although the cause and pathophysiology of peripheral neuropathy were different in MS and in NMO. There might be a group of NMO who were affected simultaneously in the central and peripheral nervous tissues.

Clinical and Electrophysiological Characteristics of Meralgia Paresthetica

Background: Meralgia paresthetica (MP) is a mononeuropathy affecting the lateral femoral cutaneous nerve. The disease is often diagnosed clinically, but electrophysiological tests play an important role. The aim of this study is to clarify clinical characteristics of MP as well as the role of sensory nerve conduction study (NCS) in the diagnosis of MP. Methods: Sixty-five consecutive patients with clinical diagnosis of MP between March 2001 and June 2012 were retrospectively reviewed at a single tertiary center. General demographics, clinical characteristics and sensory NCS findings were investigated. Measurements of sensory NCS included the baseline-to-peak amplitude, side-to-side amplitude ratio and the conduction velocity. To compare between the normal and abnormal NCS groups, independent t-tests and chi-square test were performed. Results: Sixty-five patients had male predominance (56.9%) with mean age of 48.4±13.4 years (range: 16-75). Seven patients (13.5%) had undergone operation or procedure before the symptom onset. The sensory nerve action potentials were obtainable in 52 (80%) of 65 clinically diagnosed MP patients. Sensory NCS revealed abnormalities in 38 patients (73.1%), and others (n=14, 26.9%) showed normal findings. Between the normal and abnormal NCS groups, there is no statistically significant difference on demographics or clinical features. Conclusions: We clarify the clinical features and sensory NCS findings of MP patients. Due to several limitations of sensory NCS, the diagnosis of MP could be accomplished both clinically and electrophysiologically.

Correlation between Preoperative Kimura Inching Studies and Intraoperative Findings during Endoscopic-Assisted Decompression of the Ulnar Nerve at the Elbow

During the evolution of the senior author's technique of ulnar nerve transposition to in situ decompression for ulnar neuropathy at the elbow, nerve conduction studies (NCS) including the Kimura inching method were performed preoperatively in an effort to ensure that all potential sites of compression were investigated intraoperatively. The purpose of this study is to compare the results of the Kimura inching technique with the intraoperative findings noted during decompression of the ulnar nerve at the elbow. The medical records of consecutive patients who underwent in situ decompression of their ulnar nerves combined with endoscopic examination between March and December of 2009 were retrospectively reviewed. The site of ulnar nerve compression noted using the Kimura inching technique was compared with the intraoperative findings. Twelve consecutive patients (four with bilateral symptoms) underwent endoscopic ulnar nerve compression in the study period for a total of 16 cases analyzed. In 12 cases, the Kimura method localized the site of compression to Osborne's bands and/or the aponeurosis of the flexor carpi ulnaris (FCU). Intraoperatively, compression was noted at Osborne's bands, the FCU aponeurosis, and/or the FCU) muscle proper in all 16 patients. There was partial or full correlation between the nerve conduction data and intraoperative findings in 13/16 cases. There was good but not perfect agreement between the NCS and intraoperative findings, perhaps because transcutaneous NCS are less accurate when a nerve is surrounded by muscle. The information obtained in this study is valuable when planning surgery to address ulnar nerve compression.

Non-demyelinating, reversible conduction failure in a case of pharyngeal–cervical–brachial weakness overlapped by Fisher syndrome

Pathophysiologically, Guillain–Barré syndrome is divided into demyelinating and axonal subtypes. Recent studies have shown that serial nerve conduction studies (NCSs) are required to differentiate a demyelination–remyelination pathophysiology from one with axonal nodal reversible conduction failure. Cases with an overlap of pharyngeal–cervical–brachial weakness and Fisher syndrome (PCB/FS) are uncommon; the NCS findings of such cases have not been well described and the evolution of the NCS findings has not been previously studied. We describe the clinical features and serial NCS findings of a patient with PCB/FS. The evolution of abnormalities in NCS reflected a clinical pattern of weakness that progressed from the top of the body and descended toward the legs, and terminated before reaching the legs. The amplitudes of motor and sensory potentials were decreased, as is consistent with acute motor-sensory axonal neuropathy. However, the amplitudes recovered without the appearance of dispersed potentials seen in remyelination, implicating the pathophysiology of nodal reversible conduction failure. Together with the electrophysiological evidence of the pathophysiology of nodal reversible conduction failure in previously reported PCB patients and FS patients, our case suggests that PCB, FS and PCB/FS fall in a continuous spectrum with axonal GBS subtypes.

Neuropathies associated with oxaliplatin therapy

Neuropathies associated with oxaliplatin therapy

The significance of folate deficiency in alcoholic and nutritional neuropathies: Analysis of a case

ObjectiveTo elucidate the significance of folate deficiency in alcoholic and nutritional neuropathies. MethodsWe preformed a comprehensive clinical screening of a patient with chronic alcoholism who manifested neuropathy, macrocytic anemia, liver dysfunction, and folate deficiency. ResultsA 33-y-old woman with chronic alcoholism presented with acutely progressive glove- and stocking-type sensorimotor polyneuropathy. Although an episode of neuropathy preceded the current episode by 2 y, its cause was never determined. The findings of nerve conduction studies were indicative of axonal neuropathy. Laboratory findings revealed macrocytic anemia and liver dysfunction. Her serum level of folate was reduced, whereas thiamine, riboflavin, and cobalamin levels were within normal range. The neuropathy and anemia showed gradual recovery after the initiation of folic acid supplementation. ConclusionsThis case study indicates that folate deficiency should be monitored closely in patients with chronic alcoholism and associated malnutrition. Additionally, folate deficiency should be considered as a differential diagnosis of neuropathy.

Assessment of the Medial Dorsal Cutaneous, Dorsal Sural, and Medial Plantar Nerves in Impaired Glucose Tolerance and Diabetic Patients With Normal Sural and Superficial Peroneal Nerve Responses

OBJECTIVEThis study evaluated the nerve conduction study (NCS) parameters of the most distal sensory nerves of the lower extremities—namely, the medial dorsal cutaneous (MDC), dorsal sural (DS), and medial plantar (MP) nerves—in diabetic (DM) and impaired glucose tolerance (IGT) patients who displayed normal findings on their routine NCSs.RESEARCH DESIGN AND METHODSStandard NCSs were performed on healthy control (HC), DM, and IGT groups (N = 147). The bilateral NCS parameters of the MDC, DS, and MP nerves were investigated. The Toronto Clinical Scoring System (TCSS) was assessed for the DM and IGT groups.RESULTSThe mean TCSS scores of the IGT and DM groups were 2.5 ± 2.3 and 2.8 ± 2.2, respectively. No significant differences between the two groups were observed. After adjustment of age and BMI, the DM group showed significant NCS differences in DS and MDC nerves compared with the HC group (P < 0.05). These differences were also exhibited in the left DS of the IGT group (P = 0.0003). More advanced NCS findings were observed in the DM group. Bilateral abnormal NCS responses in these distal sensory nerves were found in 40 and 16% of DM and IGT patients, respectively.CONCLUSIONSThese results showed that the simultaneous assessment of the most distal sensory nerves allowed the detection of early NCS changes in the IGT and DM groups, even when the routine NCS showed normal findings.