Figen Guney

Pregabalin versus gabapentin in the treatment of neuropathic pruritus in maintenance haemodialysis patients: a prospective, crossover study.

Aim:  Pruritus is common in dialysis patients. Peripheral neuropathy is also prevalent in this patient population. However, the role of neuropathy in the genesis of uraemic itch has not been adequately studied to date. Therefore, we aimed to investigate the effects of gabapentin and pregabalin on uraemic pruritus along with neuropathic pain in patients receiving haemodialysis.

Colchicine toxicity in end-stage renal disease patients: a case-control study.

Colchicine has been used in a number of disorders. Because colchicine is partially excreted from the kidney, there is a need for dose reduction in case of renal functional impairment. There are no data with regards to safe dosing schedule of colchicine in hemodialysis patients. We aimed to evaluate adverse effects of colchicine use in a hemodialysis cohort. We screened hemodialysis patients who were using colchicine for any reason. All patients were interviewed regarding possible toxicities of colchicine use and were examined with a special focus on neuromuscular system. Creatine kinase and myoglobin were used to detect any subclinical muscle injury or rhabdomyolysis, respectively. Twenty-two maintenance hemodialysis patients who were on colchicine for more than 6 months and 20 control hemodialysis patients not using colchicine were included in the study. Four of 22 patients were using 0.5 mg/day, 4 patients were using 1.5 mg/day, and 14 patients were using 1 mg/day colchicine. Mean duration for colchicine use was 8.9 ± 8.2 years. There was no difference between the groups in terms of myoneuropathic signs and symptoms and blood counts except for white blood cell count, which was significantly higher in patients on colchicine. Serum creatine kinase (56.3 ± 39.5 and 52.1 ± 36.1 for colchicine and control groups, respectively, P = 0.72) and myoglobin (191.4 ± 108.8 and 214.6 ± 83.5 for colchicine and control groups, respectively, P = 0.44) levels were not different between the groups. We conclude that in a small number of haemodialysis patients who were apparently tolerating colchicine, detailed assessment revealed no evidence of sublinical toxicity when compared with controls.

Pattern‐reversal Visual Evoked Potentials in Patients with Newly Diagnosed Epilepsy

Summary:  Purpose: The possible occurence of evoked potential (EP) abnormalities in patients with newly diagnosed epilepsy has been little investigated. The main purpose of the present study was to investigate possible changes in pattern‐reversal visual evoked potential (P‐VEP) responses in newly diagnosed epilepsy patients.

CONDUCTION VELOCITY DISTRIBUTION: EARLY DIAGNOSTIC TOOL FOR PERIPHERAL NEUROPATHIES

In order to get early information on the functional state of smaller myelinated fibers this article investigated the applicability of conduction velocity distribution on compound action potential recorded in experimentally demyelinated frog sciatic nerve. Conduction velocity distribution histograms were estimated by using the mathematical model the authors enhanced. The results suggest that by using appropriate conduction velocity distribution model the diagnosis time in demyelinating neuropathy may be shortened at least three times as compared with conventional conduction velocity assessment. Therefore, it may be concluded that a well-defined model designed for the estimation of the conduction velocity distribution may be used as a diagnostic tool for the early phase of peripheral demyelinating neuropathies.

Blink Reflex Alterations in Diabetic Patients with or without Polyneuropathy

The main aim of this study is to evaluate the role of blink reflex for early diagnosis of cranial neuropathy in diabetic patients with or without polneuropathy. Ninety-five diabetic patients were included in the present study for the evaluation of blink reflex. The diabetic patients were divided into two groups according to having diabetic neuropathy or not. Both R1, R2i and R2c latencies in all diabetic patients with or without polyneuropathy were prolonged relative to controls and the differences were statistically significant (p < .001). R1 latencies in diabetic patients with polyneuropathy were prolonged relative to diabetic patients without polyneuropathy and the differences were statistically significant (p < .001). These findings presumably reflect that facial nerve is severly involved in diabetic polyneuropathy. Finally blink reflex is of value in detection of clinically silent intraaxial brainstem functional abnormalities or extraaxial lesions in diabetic patients before peripheral neuropathy.

First case report of neurobrucellosis associated with hydrocephalus

Brucellosis is a common zoonosis in many parts of the world, including Mediterranean and Middle Eastern countries. The disease is primarily related to occupations at risk, such as veterinarians, farmers, laboratory technicians, abattoir workers, and others working with animals and their products. Neurologic complications of brucellosis are quite rare, ranging from 1.7 to 10% of those infected. To date, no cases of neurobrucellosis with hydrocephalus have been reported. A 38-year-old right-handed farmer complained of headaches, nausea, vomiting, gait disturbance, and sweating for 2 days. He also complained of bilateral hearing loss of 4 months duration. On neurologic examination, dysmmetry, dysdiadochokinesis, ataxia on the left, and bilateral sensorineural hearing loss existed. On cranial MRI, a communicating hydrocephalus was noted. Because the patient consumed fresh sheep cheese and was a farmer, brucellosis was considered in the differential diagnosis. Brucella agglutination was positive with a 1/320 titer in the blood and a 1/80 titer in the cerebrospinal fluid. Ceftriaxone, doxycycline, and rifampicin were administered and by the fourth week of treatment, the ataxia was markedly improved, and the patient was able to walk without support. His cranial MRI demonstrated a total regression of the hydrocephalus. As a result, we suggest that neurobrucellosis should be considered in patients with hydrocephalus, especially if they live in an endemic area for brucellosis, even in the absence of other systemic signs.

Posterior interosseous nerve syndrome caused by the use of a Canadian crutch.

Compressive neuropathy of the posterior interosseous nerve (PIN) results mainly from soft tissue masses and tumors.1,5 Extrinsic compression of the PIN is unusual. The present case report may therefore be of interest. A 67-year-old woman presented, in July 2002, with a 1-year history of the gradual onset of weakness of finger extension of the right hand at the metacarpophalangeal joints. There were no sensory complaints. Following the left hip surgery she had undergone in 1997, a single Canadian crutch was prescribed on the right side for ambulation. In June 2002, she was advised to discontinue the use of the crutch, with a slight return of function of the right thumb. There was no previous history of trauma, strenuous arm use, or any predisposing metabolic disease. On examination, there was no palpable mass dorsally in the elbow region. No muscle hypertrophy was observed. Right extensor carpi ulnaris and extensor digitorum communis showed grade 3 weakness on the Medical Research Council (MRC) scale. Radial deviation during wrist extension was noted. There was MRC grade 2 weakness of the right extensor indicis proprius, extensor pollicis longus and brevis, and abductor pollicis longus muscles. Sensory examination and deep tendon reflexes were normal. The forearm cuff of the crutch exerted considerable pressure on the proximal dorsal area of the right forearm. The patient did not return for a follow-up examination. Electrodiagnostic testing was performed on a Neuropack MEB-5504 electromyograph (Nihon-Kohden, Tokyo, Japan). Skin temperature was 32°C at the dorsum of the right wrist. Motor and sensory nerve conduction studies of the right median and ulnar nerves were normal. Motor and sensory nerve conduction studies of the right radial nerve were performed with the patient supine, shoulder abducted to 10°, elbow flexed by 10–15°, forearm fully pronated, and wrist in a neutral position. Jebsen’s method was used for motor nerve conduction.2 A concentric needle electrode was inserted into the extensor indicis proprius muscle, lateral to the extensor carpi ulnaris tendon and 4 cm proximal to the ulnar styloid. Surface electrodes were used for stimulating the nerve at 4 cm proximal to the site of needle insertion and 6 cm proximal to the lateral epicondyle between the brachialis and brachioradialis muscles. A motor response could not be elicited by stimulation of the right radial nerve. For superficial radial sensory nerve conduction study, the recording disc electrodes were placed 4 cm apart at the base of the web between the thumb and index finger. Surface stimulating electrodes were placed on the ridge of the radius 12.5 cm from the recording cathode. The latency was measured from stimulus onset to the negative peak of the sensory nerve action potential (SNAP). Superficial radial sensory nerve conduction was normal. Conduction studies were not done on the left side. Concentric needle electromyography (EMG) revealed dense fibrillation potentials and positive sharp waves (3 ), increased numbers of polyphasic motor unit potentials, and discrete activity in the recruitment pattern of the right extensor carpi ulnaris muscle; similar but less severe changes were found in the right extensor digitorum communis. There were 2 fibrillation potentials and positive sharp waves in the right extensor indicis proprius, but no voluntary motor unit potentials. The right triceps, brachioradialis, extensor carpi radialis, and abductor pollicis brevis muscles were normal. The clinical and electrophysiological findings in our patient indicate a right PIN syndrome probably caused by extrinsic compression due to the use of a Canadian crutch. A similar case has been reported, but the localization was unclear because the radial SNAP was abnormal and the patient had had polio previously.4 Although commonly known as a Canadian crutch, the correct name of the crutch used by that patient, as well as ours, is the Lofstrand crutch. The true Canadian crutch, having two half-cuffs, supports the forearm and mid-arm, whereas a Lofstrand crutch consists of a forearm piece bent posteriorly above the handpiece. The forearm piece, adjustable in length, extends to 2 inches below the elbow, where a forearm cuff with a narrow anterior opening is attached.3 Ours is the second reported case, to our knowledge, of a PIN syndrome caused by an