Association between myasthenia gravis and Alzheimer's disease

INTRODUCTION

Myasthenia gravis (MG) and Alzheimer's disease (AD) are two of the most important diseases where the dysregulation of acetylcholine activity plays a crucial role. In the first, this dysregulation happens at the level of the neu-romuscular junction and in the second, in the central nervous system (CNS).

AIM

To analyze the possible relationship between these two pathologies, analyzing the prevalence and the odds ratio of AD within patients previously diagnosed with MG. We will compare these data with respect to the prevalence of AD in the general population.

PATIENTS AND METHODS

We examined the data obtained by the electronic medical records of patients in the health care system of Castilla La Mancha using the Natural Language Process provided by a clinical platform of artificial intelligence known as the Savana Manager?.

RESULTS

We identified 970,503 patients over the age of 60 years, of which 1,028 were diagnosed with MG. The proportion of the patients diagnosed with AD within this group (4.28%) was greater than the rest of the population (2.82%) (p = 0,0047) with an odds ratio of 1.54 (confidence interval at 95% 1.13-2.08; p = 0.0051) without finding significant differences in the bivariate analysis for the rest of the most important actual known risk factors for AD.

CONCLUSION

Our results suggest that there might be an increase in the prevalence of AD in patients previously diagnosed with MG.

[Iodinated contrast-induced encephalopathy: a pathology that must be borne in mind when carrying out endovascular examinations]

INTRODUCTION

In recent years there has been an increase in the number of endovascular examinations in the study of both cardiovascular and cerebrovascular diseases. One very infrequent complication is neurotoxicity due to contrast, and it must be suspected within the context of a neurological deficit following such examinations in order to be able to diagnose it.

CASE REPORT

A 61-year-old male who presented an epileptic attack and later deficit in the left hemisphere following diagnostic arteriography. After ruling out the possibility of an urgent vascular pathology, he was submitted to a magnetic resonance brain scan with the suspicion of this condition. The clinical signs and symptoms were limited to 72 hours with cortisone therapy.

CONCLUSIONS

Contrast-induced encephalopathy covers a wide range of clinical features which, in the vast majority of cases, are self-limiting to 24-72 hours, and within the context of neuronal damage following contrast infusion. Its prognosis is excellent, and diagnostic suspicion is crucial in its treatment.

[Drug-induced movement disorders]

INTRODUCTION

Pharmaceutical preparations with the capacity to block dopamine receptors at the brain level quite often cause secondary movement disorders, but are not the only cause. These movement disorders can be due to a poor or difficult capacity to carry out movements similar to the type observed in idiopathic Parkinson's disease (parkinsonism secondary to drugs) or also because of excess movement with acute or chronic dystonic or choreic clinical pictures. Why the same drugs cause apparently opposing effects is not altogether clear, although it is supposed that individual factors related to the pharmacokinetics, pharmacodynamics and sensitivity of different types of sub-receptors play a crucial role.

DEVELOPMENT

We describe the most frequent groups of symptoms, divided into two parts depending on whether the disorder is hyper- or hypokinetic, and the drugs that are most commonly responsible for those clinical pictures are also discussed. The most frequent disorders caused by excessive movement are acute dyskinesia, akathisia and tardive dyskinesia. The disorder caused by scarcity of movement is a parkinsonian picture that it may be impossible to distinguish from idiopathic Parkinson's disease.

CONCLUSIONS

An awareness of the possible existence of these disorders is essential for the clinical suspicion and diagnosis. On most occasions, withdrawing the causing drug reverts the symptoms without the need for complicated or costly diagnostic studies.

[Chronic progressive external ophthalmoplegia: clinical and electromyographic manifestations in a series of cases]

INTRODUCTION

Chronic progressive external ophthalmoplegia (CPEO) is a common mitochondrial disease. The different conditions in this group of diseases overlap clinically, enzymatically and genetically. There is no effective treatment. Ptosis improves with corrective surgery involving tarsorrhaphy as a palliative measure.

CASE REPORTS

Code numbers were examined in a retrospective study conducted in order to search for patients with ptosis or ophthalmoplegia who had either visited or been admitted to the neurology department over the last 10 years. Data concerning these patients' clinical features and results of complementary tests were collected. Six patients with CPEO were identified, five of whom were females. Ages ranged from 44 to 72 years. All the patients had ptosis, although 50% were asymmetric. Half of them reported mild dysphagia while swallowing liquids. Levels of creatine phosphokinase and acetylcholine antireceptor antibodies were normal. Half the patients showed increased jitter and a muscle biopsy revealed that five of them had ragged red fibres. The most frequent enzyme deficit was complex I and IV deficiency. There were no familial forms; the most common genetic anomaly was single deletion in the mitochondrial deoxyribonucleic acid.

CONCLUSIONS

In cases of ptosis and ophthalmoplegia that do not respond to anticholinesterases, knowledge of this condition makes it possible to avoid the use of immunosuppressant drugs, which have important side effects.

[Recurrent Tolosa-Hunt syndrome with normal neuroimaging. A report of three cases]

INTRODUCTION

Tolosa-Hunt syndrome is caused by an unspecific inflammation in the cavernous sinus or superior orbital fissure. Recurrence occurs in 40% of cases. Magnetic resonance (MR) of the head and orbital phlebography can reveal characteristic data, although diagnosis is reached by exclusion according to International Headache Society criteria. Corticoids are the preferred treatment, since their use gives rise to the disappearance of the clinical condition in a few days.

CASE REPORT

We describe the cases of three patients with recurrent Tolosa-Hunt syndrome and MR images of the head with normal contrast. Case 1: a 52-year-old male with paralysis of the oculomotor nerve with recurrence on the contralateral side. Case 2: a 42-year-old female with recurrent paralysis of the abducent nerve. Case 3: a 34-year-old male with involvement of the oculomotor nerve, optic nerve and the first branch of the trigeminal nerve with recurrence of the ophthalmoplegia. In all cases the clinical symptoms disappeared with the use of corticoid therapy.

CONCLUSIONS

The oculomotor disorder is produced by nerve infiltration and not by compression. The time for recurrence varies largely, and the clinical condition in the recurrence is usually milder owing to the fact that diagnosis is reached and treatment is started earlier. The absence of alterations in the MR of the head does not rule out the existence of Tolosa-Hunt syndrome, even in cases of recurrence, and these disorders therefore should not be included in the diagnostic criteria.

[Horner syndrome as the first symptom of nasopharyngeal cancer. Two case reports]

INTRODUCTION

Horner syndrome (HS) is produced by damage to the oculosympathetic pathway and gives rise to palpebral ptosis, enophthalmos and myosis. Anhidrosis also occurs in cases in which the lesion is located before the separation of the vasomotor and sudomotor fibres at the start of the internal carotid artery. Nasopharyngeal cancer may damage the cranial nerves, mainly in the cavernous sinus, and very few cases of HS due to infiltration of the tumour into the parapharyngeal space have been reported.

CASE REPORTS

Case 1: a 67-year-old male with a 10-day history of HS on the left side without anhidrosis. The aetiological study revealed a nasopharyngeal lymphoepithelioma; the tumour became smaller and HS disappeared following treatment with chemotherapy. Case 2: a 48-year-old male with a 1-week history of HS without anhidrosis, and a 2-month history of deafness and pain in the right ear. The aetiological study showed a nasopharyngeal lymphoepithelioma and serous otitis. The tumour became smaller and HS disappeared following treatment with chemotherapy.

CONCLUSIONS

It is important to carry out studies of the nasopharynx in patients with this syndrome to allow early diagnosis and treatment of a region that is not readily available for direct examination. The existence of an associated pathology in the ear or the paranasal sinuses strongly suggests that its origins lie in the nasopharynx.

[Mumps meningitis: a case mix in a Neurology Department]

INTRODUCTION

Parotiditis is a viral infection that produces a non-suppurative inflammation of the parotid glands, although it may affect other salivary glands, the testicles, meninges and the pancreas. Clinical meningitis appears in 1-10% of cases, normally between the 4th and the 10th day after infection of the parotid glands. In this study, we analyse the clinical and analytic characteristics of the patients admitted to our Neurology Department over the last 12 years.

CASE REPORTS

A retrospective study was conducted by analysing the hospital discharge reports. The eligibility criterion was the existence of an acute meningeal syndrome linked to the presence of positive IgM titres for the parotiditis virus. In all, 13 cases were found, with a mean age of 16.5 years, and most of them were males (92.3%). Parotiditis preceded meningitis in all our patients with an average of 8.3 days, while orchiepididymitis, when it occurred, appeared at the same time or after meningitis. Analysis of the cerebrospinal fluid showed a lymphocyte profile with glycorrhachia above 40%, except in two cases that showed a non-persistent neutrophilic profile. There was a transient 30.7% reduction in prothrombin time in the patients. No sequelae were observed.

CONCLUSIONS

Vaccination campaigns have drastically reduced the number of cases of meningitis due to this germ since the second half of the 90s. This virus must be borne in mind in cases of meningitis in young males who come from underdeveloped countries.

[An analysis of the health care activity of on-call neurologists and its repercussions in the hospital]

INTRODUCTION

The implementation of an on-call neurology service at our hospital prompted us to analyse the health care it offers.

PATIENTS AND METHODS

We conducted a retrospective descriptive study by reviewing the status report of the on-call services performed between 15 April 2002 and 14 April 2003. The data collected included the age, sex, day of the week, month, requesting service, destination and pathology grouped under different codes to facilitate their later analysis.

RESULTS

A total of 1910 patients were attended with a mean age of 53 and with no differences between sexes. The service that most often requested evaluation was casualty with over 80% of cases. The most frequently involved pathologies were headaches (19.7%), followed by ischemic strokes (16.1%) and epilepsy (13.4%). In 12.3% of cases no neurological pathology was observed. The percentage of direct hospital discharges was 29.16%, while that of admissions to neurology was lower (23.56%). Patients requiring further follow-up visits to Neurology were remitted normally (12.56%), compared to those who were in need of preferential treatment (4.45%).

CONCLUSIONS

The need for a duty neurologist has provided our hospital with a better evaluation of neurological pathologies and a more rational use of complementary tests. Many of the patients who were evaluated were given a direct hospital discharge. This has led to a drop in the number of admissions to Neurology by almost 30% and a reduction in the mean length of time spent in hospital.

[Transcranial Doppler during transient global amnesia]

INTRODUCTION

Transient global amnesia is a syndrome mainly characterised by an anterograde memory deficit, which disappears in less than 24 hours without leaving any kind of sequelae. Its aetiopathogenesis is still unclear. The ischemic theory became important after hypoperfusion was observed in the mesial region of the temporal lobe using different imaging techniques, although recently the use of diffusion-weighted magnetic resonance imaging by other authors has not revealed these alterations in the cerebral blood flow.

CASE REPORT

We report on a transcranial Doppler study carried out in a female patient during the acute phase of the amnesia, with no evidence of hemodynamic alterations or significant asymmetries. Repeating the test after clinical recovery offered values that were similar to those of the previous study.

CONCLUSIONS

It is posited that the basis of this process would not be related to ischemia but instead to a mechanism enabling spreading neurogenic depression that is similar to that which takes place during a migraine attack. Treatment with antiplatelet drugs would not, therefore, be recommended but calcium antagonists or beta blockers would be useful in preventing the clinical picture from being repeated.