Hemodialysis-related headache and how to prevent it.

BACKGROUND AND PURPOSE: Hemodialysis (HD) may have some adverse effects on the nervous system. Headache is the most commonly reported neurological symptom amongst HD patients. Our aim was to determine the frequency, clinical characteristics and triggering factors of HD-related headache (HRH) and to evaluate preventive strategies for reducing HRH. METHOD: In all, 494 patients were included. Comparative controls (CC) were classified within the same patients without headache. Arterial systolic/diastolic blood pressure, blood urea nitrogen (BUN) and creatinine were correlated before/after one HD. The urea reduction ratio during the dialysis session was determined. RESULTS: A total of 175 patients (35.4%) with a mean age of 57.3 ± 15.7 years were diagnosed with HRH. HRH was more common in males (P < 0.001). Headache was started a mean of 2.90 ± 0.86 h after the HD. The common localization of pain was reported to be bifrontal in 41.7% (n = 73). The mean duration of headache was 6.22 ± 7.8 h, with a duration of ≤4 h reported by 64.0% of patients. The mean Visual Analog Scale score was 5.64 ± 2.05. The differences between pre/post-dialysis BUN values were 94.6 ± 31.1 in HRH patients and 86.8 ± 28.5 in the CC group (P = 0.006). The systolic blood pressure difference between the pre/post-dialysis measurements was 22.4 ± 16.5 mmHg in HRH patients and 12.8 ± 19.4 mmHg in CC(P < 0.001). Patients with HRH had significantly higher mean systolic and diastolic blood pressure pre-dialysis values (systolic, P = 0.002; diastolic, P < 0.001). The differences in systolic/diastolic blood pressure between pre/post-dialysis were higher in the HRH group (P < 0.001, P = 0.001, respectively). CONCLUSION: Regulating the frequency and timing of dialysis may provide better management in HRH with high BUN levels and high pre-dialysis blood pressure.

Somatosensory evoked blink response in hemifacial spasm and peripheral facial palsy.

Somatosensory blink response (SBR) is produced by electrical stimulation of peripheral nerves or skin areas remote from the face. We investigated the presence of SBR in cases with hemifacial spasm (HFS) and peripheral facial palsy (PFP). Fifty-seven cases of HFS, 54 cases of PFP and 39 normal subjects were included in the study. A routine blink reflex study was performed in all subjects. Supramaximal stimulation of the median nerve was given ipsilateral to the either spasm or paralytic side for SBR. Recordings were made at the orbicularis oculi (o.oc) bilaterally and ipsilaterally at the orbicularis oris (o.or) muscles. SBR was elicited in 12 of 39 control subject. Twenty four of 48 HFS cases were SBR positive. Twelve of them had o.or response. An SBR was elicited at the ipsilateral o.oc in 35 of 46 patients with PFP with synkinesia. Twenty-six patients had an SBR at the ipsilateral o.or. In the 13 patients with PFP without synkinesia only 3 people had an SBR. SBR positivity was seen more often in PFP with synkinesia than in cases with HFS. SBR if positive spreads to the lower part of the face in most of cases with HFS and PFP with synkinesia.

Relationship between reflex excitability and symptom duration in hemifacial spasm.

Changes in excitability and symmetry characteristics have been analyzed with blink reflex recovery curve method applied with dual stimuli at 200, 600 and 1000 ms in patients with hemifacial spasm (HFS), spasm duration shorter than 1 year (HFS 1), spasm duration longer than 8 years (HFS 2), and control group. When compared with controls, while HFS cases with short symptom duration had significant decreases in inhibition at 200 ms in the spasm and healthy sides, those with long symptom duration had this finding only in the spasm side at the 200 ms interval. When HFS groups were compared with each other, in cases with HFS 1, decreased inhibition in the spasm side was significant at 200 and 600 ms, while this was significant only at 200 ms in HFS 2 cases. HFS groups were not found to be different in terms of R2 recovery grade. In conclusion, in cases with HFS, decreased inhibition attributed to facial motor neuron and brain stem interneurons is more predominant on the side of the spasm and this was shown to be present also, to some extent, in the contralateral side. It can be said from our findings that the abnormalities of the blink reflex recovery do not progress in cases with HFS when the symptom duration becomes longer.

Haemodialysis-related headache.

Dialysis may induce severe headache as a result of a large amount of water and electrolyte shifts. It is important to recognize it because it can be a great problem to the patient and changing dialysis parameters or methods can prevent it. In this study we investigated the frequency and clinical characteristics of headaches occurring during haemodialysis (HD). Thirty female and 33 male patients with chronic renal failure on regular dialysis for at least 6 months in the HD unit of the Internal Medicine Department from 1996 to 2000 participated in the study. The dialysis solution contained acetate in 35 patients and bicarbonate in 28 patients. In all patients capillary dialysers and Cuprophan membranes were used and every session of dialysis lasted 4 h. All patients received the same questionnaire and they were visited randomly. Dialysis headache (DH) diagnosis was made according to the criteria of the International Headache Society. Patients with primary headache and under drug treatment during HD, which can cause headache, were excluded from the study. The frequency of DH, its relation to gender, age, dialysis technique and parameters and its features were investigated. DH was detected in 48% (n = 30) of the study group. Compared with dialysis solutions, no difference was found between patients with and without DH. The difference in the pre- and post-dialysis value of urea in patients with DH was statistically significant (P < 0.05). Patients with DH showed significantly higher mean systolic and diastolic blood pressure predialysis values in comparison with patients without DH (systolic, P < 0.001; diastolic, P < 0.01), whereas post-treatment values did not differ between the two groups. Fronto-temporal location, moderate severity, throbbing quality and short duration (<4 h) were the most prevalent features of DH in patients.

Hepatitis B vaccine related-myelitis?

We present four incidental cases that developed partial myelitis following the administration of hepatitis B vaccine in 1998. The first two cases, a 33-year-old man and a 42-year-old woman developed progressive sensory symptoms without motor involvement within 4 weeks following the vaccination. Their magnetic resonance imaging (MRI) disclosed similar lesions consistent with myelitis at their cervical spinal cord. A comparable inflammatory lesion was seen at the T9-T10 levels of the spinal cord in the third case, who was a 40-year-old woman presenting with numbness in her legs and urinary retention following the vaccination. The fourth case who was a 42-year-old woman, presented with sensory symptoms in her left extremities, which developed 3 months after the vaccination. Her MRI showed a hyperintense lesion at C6. She also had two tiny lesions in her cranial MRI. In all cases, there was no history of preceding infections and no clinical evidence suggestive of any other disorders that may cause myelopathy. All patients recovered completely within 3 months with the exception of the third patient who developed new neurological symptoms after 12 months. Similar clinical and imaging presentation of myelitis following hepatitis B vaccination within a 1 year period with no other demonstrable clinical and laboratory evidence for any other disorder raise the probability of a causal link between these two events.