Reversal of iron deficiency anemia-induced peripheral neuropathy by iron treatment in children with iron deficiency anemia

The effects of iron deficiency anemia (IDA) on nerve conduction and efficiency of iron therapy were investigated by peripheral nerve-electrophysiological measurements. Eighteen children (10 boys, eight girls; mean age 31 +/- 1.3 months) with IDA and 12 healthy children (six boys, six girls; mean age 29 +/- 1.3 months) were enrolled into the study. Nerve conduction velocity was measured in the median and posterior tibial nerve. After nerve conduction values were determined in the patients and controls, 6 mg/kg/24 h ferrous sulphate was given orally to the patients for 3 months and nerve conduction velocity tests were performed again. Median/motor and sensory nerve conduction velocity and tibial/motor nerve distal-amplitute values of children with IDA were lower than for the control group (p < 0.05, p < 0.01 and p < 0.001 respectively). With iron supplementation these values increased to the normal levels and even higher than control levels for some parameters. In correlation studies between whole blood parameters and nerve conduction velocity results, there was a correlation between median/sensory nerve conduction velocity values and serum iron levels. Additionally there was a correlation between some nerve conduction velocity values and age. In conclusion, the evidence from this preliminary study suggests that peripheral neuropathy may develop in children with IDA. Peripheral neuropathy symptoms in these patients may be improved by iron therapy.     

Motor nerve conduction studies on children with spinal muscular atrophy

Median and posterior tibial motor nerve conduction studies were performed on 10 children with spinal muscular atrophy (SMA). Three patients with SMA type I, in whom rapid deterioration occurred, showed reduced motor nerve conduction velocity and a remarkably low M-wave amplitude in both nerves. In type II and III patients, the motor nerve conduction velocity was normal in the median nerve, although the M-wave amplitude was small in the tibial nerve. In four patients, a reduction of the M-wave amplitude was observed as clinical symptoms advanced. These findings may suggest that motor conduction studies in spinal muscular atrophy provide complementary information for understanding the pathogenesis and are also useful to clarify the heterogeneity of this disease.     

Novel mutations in SH3TC2 in a young Japanese girl with Charcot‐Marie‐Tooth disease type 4C

Charcot‐Marie‐Tooth disease type 4C (CMT4C) is an autosomal recessive demyelinating form of CMT characterized clinically by early onset and severe spinal deformities, and is caused by mutations in SH3TC2. We describe the case of a 10‐year‐old Japanese girl diagnosed with CMT4C. The patient developed progressive foot deformities such as marked pes cavus and ankle contracture, with mild muscle weakness in both legs, and generalized areflexia. On electrophysiological studies, motor nerve conduction velocity ranged from 22.3 m/s in the tibial nerve to 48.2 m/s in the median nerve. Sensory nerve conduction velocity ranged from 30.3 m/s in the sural nerve to 52.8 m/s in the median nerve. Sequence analysis of candidate genes identified two novel heterozygous mutations, c.229C>T and c.2775G>A, in SH3TC2. The patient was diagnosed as having CMT4C with novel mutations, making this the first documented Japanese pediatric case.     

Slow Nerve Conduction Velocity in Cretins

The ulnar and posterior tibial conduction velocities were measured in 6 untreated and 3 treated cretins. In 4 of the untreated patients, the conduction velocity of both nerves was slower than normal; in 1 patient the ulnar and in the other the posterior tibial nerve conduction velocity was slower than normal. There was a close agreement between bone age and the age corresponding to the slow conduction velocities. The 3 treated cretins all had normal posterior tibial conduction velocities, while the ulnar conduction velocity was normal in one, slower in another, and faster than normal in the third.The slow nerve conduction velocity in cretins probably reflects a delay in maturation of the peripheral nerves. Nerve conduction velocity measurement may be a useful screening test in suspected congenital hypothyroidism, and may also prove of value in assessing response to therapy.     

PERIPHERAL NEUROPATHY IN DIABETIC CHILDREN AND ADOLESCENTS

ABSTRACT. In order to establish the general prevalence of peripheral neuropathy in diabetic children and adolescents, median motor and sensory conduction velocities and the peroneal motor conduction velocity were registered in 161 unselected diabetic children and adolescents and 55 healthy controls. The influence of the duration and the balance of diabetes on the results was analysed in the diabetic group. In the controls the age correlated positively with the median motor and sensory conduction velocity, but not with peroneal motor conduction velocity. In diabetic children, the greatest impairment was found in the peroneal motor conduction velocity, 49 patients (30 %) had a value lower than -2SD below the mean normal value. There was a correlation between the balance of diabetes based on HbA₁ and glucosuria, and median and peroneal motor conduction velocities. The median motor conduction velocity was independent of the duration of diabetes, but a correlation was found between the duration of diabetes and peroneal motor conduction velocity impairment. Motor conduction velocity determination of the peroneal nerve can be used both in revealing and following the abnormality in peripheral nervous function in diabetic children. Regular follow-up of nervous function test results may help in assessing the importance of good metabolic control in preventing diabetic complications.     

Peripheral nerve conduction abnormalities in children exposed to alcohol in utero

OBJECTIVE: We performed a longitudinal study of nerve conduction velocity to determine the effect of prenatal alcohol exposure on the peripheral nervous system.Study design We studied 17 children exposed to >2 oz of absolute alcohol/day prenatally and 13 unexposed children, identified prospectively from a cohort of pregnant women screened during prenatal care. Nerve conduction assessment was done on the median, ulnar, peroneal and tibial nerves during the newborn period and between 12 and 14 months of age. RESULTS: At both assessments the alcohol-exposed subjects had significantly slower ulnar motor nerve velocity (P=.007), smaller proximal (P=.018) and distal amplitude (P=.051). They also showed reduced tibial nerve velocity (P=.06) and a decrease in distal amplitude. CONCLUSIONS: This study demonstrates that prenatal alcohol exposure is associated with abnormalities in nerve electrical properties, and that the pattern is different from that seen in adults. Electrophysiologic abnormalities in peripheral nerves should be added to the problems found in children of alcohol abusing mothers.     

小儿运动神经传导正常值及发育规律

研究目的探讨小儿运动神经传导正常值及发育规律。研究方法１４９名０－１４岁儿童按年龄分为７组，成人组共１９人，年龄（２０－３５）岁。用神经诱发电位仪测量各受试者正中神经，尺神经，胫神经和腓神经的运动传导功能。结果６岁前神经动作电痊潜伏期随年龄增大而缩短，６岁后又渐延长，新生儿尺神经传导速度最快，其次为腓神经和正中神经，最慢为胫神经。出生后３个月，正中神经发育首先加快，３岁接近尺神经。胫神经于３个月－     

A 5‐yr follow‐up nerve conduction study for the detection of subclinical diabetic neuropathy in children with newly diagnosed insulin‐dependent diabetes mellitus

Lee S‐S, Han H‐H, Kim H. A 5‐yr follow‐up nerve conduction study for the detection of subclinical diabetic neuropathy in children with newly diagnosed insulin‐dependent diabetes mellitus. Pediatric Diabetes 20XX: 00: 000–000 Objective: To investigate the changes of peripheral nerve conduction in children with insulin‐dependent diabetes mellitus (IDDM) prospectively from diagnosis and to know how those results were related to clinical risk factors. Methods: A total of 37 patients (14 males and 23 females) aged 3–19 yr (mean 12.0 ± 3.7) with newly diagnosed IDDM underwent bilateral nerve conduction studies (NCS) of median, ulnar, posterior tibial, peroneal, and sural nerves annually for 5 yr. Results: In all, 12 patients (32.4%) showed electrophysiological evidence of polyneuropathy in at least two different nerves including the sural nerve at the diagnosis of IDDM; 20 patients (54%) had multiple (≥2) abnormalities in parameters of NCS. The most common abnormal parameters at the diagnosis were conduction velocities of peroneal motor and sural nerves. In sequential NCS over 5 yr, the percentage of abnormal nerve conduction velocities rose except within the sural nerve. Poor metabolic control, height, duration of diabetes, and older age of onset were related to the changes of parameters of NCS over 5 yr. Among those risk factors, the duration of diabetes and sustained hyperglycemia affected the parameters of NCS more frequently than others. Conclusions: Children with IDDM frequently have nerve conduction abnormalities without clinical neuropathy at initial diagnosis. The frequency of abnormalities of any attribute of nerve conduction increased over the 5 yr follow‐up. The duration of diabetes and poor glycemic control proved to be more important risk factors over 5 yr as related to the development of subclinical neuropathy.     

Function of the autonomic nervous system in children and adolescents with insulin-dependent diabetes mellitus

19 IDDM patients (m/f 9/10; ages 7-25 y.; duration of diabetes 3-20 y., mean 10 y.) have been compared to 15 healthy controls (m/f 11/4; ages 11-24 y., mean 14 y.) in respect to HRTS (heart rate response to standing), SDB (single deep breath) and Valsalva maneuvre. In the diabetics the results have been correlated to MNCV (motor nerve conduction velocities), quality of diabetic control and duration of diabetes. A questionnaire did not uncover signs or symptoms of autonomic dysfunction. Resting heart rates were significantly higher in diabetics but were unrelated to age, duration of diabetes, quality of diabetic control or MNCV. HRTS, SDB and the Valsalva maneuvre did not display statistically significant differences between diabetics and controls. Diabetic autonomic dysfunction seems to be rare in young diabetics. Routinely testing for this sequela would therefore not be justified at this stage of diabetes. On the other hand diabetic autonomic dysfunction might be harmful for the patient as regards sudden and unexpected cardiorespiratory arrest eg. during anaesthesia or bronchopneumonia. If therefore symptoms and/or signs of possible peripheral or autonomic dysfunction are present special investigations (eg. HRTS) are indicated.     

脊髓栓系综合征电生理检测特点及临床意义

利用电生理检测技术,评价脊髓栓系综合征患儿神经功能改变。方法对ＴＣＳ患儿组及对照组行胫后神经体感诱发电位、胫后神经及腓总神经运动神经传导速度检测。结果ＴＣＳ患儿组ＰＴＮ－ＳＥＰ检测出现皮层电位潜伏期延长,波幅下降甚至消失,部分马尾电位波幅消失;ＭＣＶ轻、中度减慢、动作电位波幅下降,甚至出现传导阻滞,病变随病情而加重。     

Electrophysiological studies (MNCV, H-RL) in full-term newborn babies

Twenty-five full-term newborns and their mothers constituted study subjects. Mothers were subjected to weight and height measurements, as well as, serum albumin and hemoglobin estimations. Offsprings were subjected to measurements of weight, crown heel length and head circumference along with motor nerve conduction velocity (MNCV) and H-reflex latency (H-RL). The MNCV was found to be significantly lower in growth retarded (FT-IUGR) babies compared to appropriately grown babies (FT-AGA) whereas H-RL was similar in both FT-IUGR and FT-AGA babies.     

Maturation of nerve conduction velocity from birth to 5 years of age

The Hoffmann monosynaptic reflex was recorded in the soleus muscle in 105 healthy children aged between 2 days and 5 years. From this the nerve conduction velocity in the proximal segment of the sciatic nerve was calculated. The tibial nerve conduction velocity (motor) was also measured in 59 of these children. The conduction velocity in the proximal and distal parts of the nerve develop in parallel and in an exponential manner but the conduction velocity in the reflex arc (afferent and efferent) is always faster than the motor conduction. Conduction time slightly but significantly decreases during the first year despite the increase in length of the nerve. Thereafter the conduction time slowly increases and by 5 years the values are similar to those in the neonatal period.     

腓骨肌萎缩症一家系报告并文献复习

目的 探讨腓骨肌萎缩症1A型的临床特点.方法 回顾分析腓骨肌萎缩症1A型一家系的临床表现、神经电生理及基因检测结果.结果 先证者为12岁男孩,因双下肢乏力就诊.患儿四肢肌张力稍减低,四肢近端肌力V级,远端肌力Ⅳ级,双下肢膝关节以下及双上肢远端肌肉对称性萎缩,四肢末端感觉稍减退,膝反射、踝反射消失,双足高弓足,病理征阴性...     

神经电生理检查在儿童药物注射性坐骨神经伤中的诊断价值

对５０例儿童坐骨神经药物注射伤损伤部位以远的神经传导速度和波幅及体感诱发电位的结果分析并进行了相关的实验研究。在检查的５０例腓神经中有２７例引不出动作电位，４１例胫神经中有６例引不出动作电位。余２３条腓神经、３５条胫神经传导速度和波幅患侧均较健侧明显减慢和降低。同时对２３例患儿行体感诱发电位检查，结果表明患侧潜伏期较健侧明显延长。实验结果证实在损伤早期动作电位波幅的改变比传导速度的改变更明显，更有诊断价值。     

SENSORY NERVE CONDUCTION VELOCITY AND VIBRATORY SENSIBILITY IN JUVENILE DIABETICS

ABSTRACT. Ludvigsson, J., Johannesson, G., Heding, L., Häger, A. and Larsson, Y. (Departments of Paediatrics and Neurophysiology, University Hospital Linköping, Sweden and Novo Research Institute, Bagsvaerd, Denmark). Sensory nerve conduction velocity and vibratory sensibility in juvenile diabetics. Relationship to endogenous insulin. Acta Paediatr Scand, 68: 739, 1979.—Sensory nerve conduction velocity (NCV) and the vibratory sense (biothesiometry) were determined in 67 children and adolescents with insulin dependent diabetes. Age at onset of diabetes varied between 1–14 years (mean ±S.D. 6.5±3.6) and the duration of diabetes between 4–17 years (7.7±3.4). Within ±3 months of the nerve function tests blood was drawn for determination of C-peptide and insulin antibodies (IgG and IRI). A low NCV (<50 m/s) in the sural nerve and/or an abnormal vibratory sense (≥1.0 microns) were found in 34 patients (50.7%). Measurable fasting serum C-peptide 0.04–0.60 pmol/ml (0.17±0.15) was found in 16 patients (23.9%). All but one patients had insulin antibodies with IgG 0.130–11.029 mU/ml (2.957±2.509) and total IRI 10–9120 μU/ml (1204±1723). In multiple regression analysis we did not find any correlation between nerve function and sex, age, or age at onset of diabetes, and there was only a weak relationship between NCV and duration. However, there was a positive correlation between NCV and C-peptide (p<0.001). Vibration sense was also better among patients with C-peptide (p<0.05). The results support the view that insulin deficiency contributes to peripheral diabetic neuropathy.     

Phenol block in the management of spastic cerebral palsy

In the present series 116 cases of spastic cerebral palsy were selected; in whom perineal care and ambulation was affected. These cases were given peripheral nerve block (obturator 110, posterior tibial 134 and median nerve 2) with 6% aqueous phenol solution. The block relieved the spastic condition, allowed better nursing care, freed the patient from the embarrassment of a contorted limb, allowed voluntary movement to take place and eased in fitment of caliper to aid further ambulation. The period of effectiveness ranged from 3 months to 18 months, with an average of 13 months. Paraesthesia occurred following 5 nerve blocks. Eleven nerve blocks had to be repeated. Ease, simplicity, safety, therapeutic benefits and economic advantages of peripheral nerve block using phenol in cerebral palsy warrant its more widespread use.     

Threshold effect in lead-induced peripheral neuropathy

We previously demonstrated a negative correlation between blood lead level and motor nerve conduction velocity in 202 asymptomatic 5 to 9-year-old children living near a lead smelter in Idaho. Blood lead levels ranged from 13 to 97 micrograms/dL. To determine whether a threshold exists between blood lead level and maximal motor nerve conduction velocity, we conducted three regression analyses on these data: a "hockey stick" regression, a logistic regression, and a quadratic regression. We found evidence for a threshold in all three analyses: at a blood level of 30 micrograms/dL in the "hockey stick" regression, at 20 micrograms/dL in the logistic, and at 25 to 30 micrograms/dL in the quadratic. Neither age, sex, socioeconomic status, nor duration of residence near the smelter significantly modified the relationship. These analyses confirm that asymptomatic increased lead absorption causes slowing of nerve conduction, but they also indicate that measurement of maximal motor nerve conduction velocity is an insensitive screen for low-level lead toxicity.     

Motor nerve conduction velocity in spinal muscular atrophy of childhood.

The ulnar and posterior tibial conduction velocities were measured in 29 children with spinal muscular atrophy, 14 of whom had the servere form of the disease. The ulnar nerve velocity was slow in 12 of the 14 severely affected infants, but normal or fast in 11 of 14 children less severely affected. The corresponding results for the posterior tibial nerve were slow velocities in 11 of 12 infants in the severe group and normal or fast in all 11 infants less severely affected. The difficulty in distinguishing infantile spinal muscular atrophy from peripheral neuropathy is emphasized.     

Subacute and chronic inflammatory demyelinating polyneuropathies in childhood

We describe five children who satisfied the clinical diagnostic criteria for chronic inflammatory demyelinating polyneuropathy. The age of onset ranged from 4 to 12 years. The pattern of their clinical courses was retrospectively divided into two subtypes. Two patients, who responded to steroids, had a monophasic course with complete recovery and withdrawal from steroids within 1 year. The slowing of the motor nerve conduction velocity gradually improved. In one case, a sural nerve biopsy specimen demonstrated no demyelination or remyelination. The other three patients had recurring relapses and required repeated or consecutive immunosuppressive therapy. Their follow-up motor nerve conduction velocities consistently remained below 35 metres/second even during remission. As there is a considerable difference in the outcome among these patients, a diagnosis of subacute inflammatory demyelinating polyneuropathy could be used for the subtype showing a favourable outcome. Although there were no factors in the initial evaluation that could distinguish between these subtypes, follow-up motor nerve conduction velocities were useful for predicting the possibility of a relapse in chronic inflammatory demyelinating polyneuropathy.     

Asian paralysis syndrome

We report 20 children admitted to the paediatric ward of a public general hospital for acute flaccid paralysis, which was bilaterally symmetrical in all cases and was associated with bulbar involvement in eight of them. Recovery was partial. Nerve conduction studies showed motor axonal neuropathy. This new disease, variously termed as non-inflammatory neuropathy/Chinese paralysis syndrome must be differentiated from Guillain-Barré syndrome (GBS) and poliomyelitis. Both GBS and Asian paralysis syndrome have bilaterally symmetrical flaccid paralysis but GBS tends to have sensory involvement, full recovery occurs in 90% of cases and nerve conduction shows demyelinating neuropathy. Asian paralysis syndrome and poliomyelitis are pure motor lesions without sensory changes and partial recovery, but poliomyelitis differs in that paralysis is asymmetrical and unequal, muscle spasm is always present in the initial stage and there are prodromal symptoms. Nerve conduction studies show anterior horn cell disease. This new entity, common in Asian populations, assumes public health importance when it mimics poliomyelitis in a country that has tried to eliminate poliomyelitis by universal immunization. To the best of our knowledge, this is the first report of Asian paralysis syndrome in children in our area.