|Year : 2013 | Volume
| Issue : 4 | Page : 245-248
Myasthenics of guntur
Nagarjunakonda Venkata sundarchary1, Amalakanti Sridhar2
1 Department of Neurology, Guntur Medical College, Andhra Pradesh, India
2 Department of General Medicine, Guntur Medical College, Andhra Pradesh, India
|Date of Web Publication||26-Nov-2013|
FF-5 pg Hostel, Government General Hospital, Guntur - 522 001, Andhra Pradesh
Source of Support: None, Conflict of Interest: None
Introduction: Myasthenia gravis (MG) is a neuromuscular disorder characterized by weakness and fatigability of skeletal muscles. There is a paucity of data regarding the disease in the state of Andhra Pradesh.
Objective: Our aim was to study the clinical profile of patients with myasthenia gravis admitted to government general hospital, Guntur, Andhra Pradesh.
Materials and Methods: We studied the cases of 36 myasthenia gravis patients admitted to the government general hospital, Guntur from September 2003 to April 2011.
Results: The median age of presentation was 40 years. Male to female ratio was 3:1. The presenting complaint was ptosis in 44.44% of the cases. The other major complaint was lower limb weakness (38.89%). Serum levels of acetylcholine receptor (AChRs) antibodies were more in males (18) than in females (9.22).
Conclusion: The median age of presentation and sex ratio matched that with the pattern in India. Ptosis may suggest a possibility of myasthenia gravis to the clinician more easily than any other complaint.
Keywords: Decremental test, myasthenia gravis, neuromuscular disease
|How to cite this article:|
sundarchary NV, Sridhar A. Myasthenics of guntur. J NTR Univ Health Sci 2013;2:245-8
| Introduction|| |
Myasthenia gravis (MG) is a neuromuscular disorder characterized by weakness and fatigability of skeletal muscles. The underlying defect is a decrease in the number of available acetylcholine receptors (AChRs) at neuromuscular junctions due to an antibody-mediated autoimmune attack. Overall, women are affected more frequently than men, in a ratio of 3:2. The cardinal features are weakness and fatigability of muscles.  Usually the eyelids and the muscles of the eyes, and somewhat less often, of the face, jaws, throat, and neck, are the first to be affected. Infrequently, the initial complaint is referable to the limbs. A decremental response to repetitive stimulation of a muscle can usually be obtained most often from the proximal limb muscles. Electrophysiological testing is almost as valuable as is testing with Neostigmine. Serum antibodies against AChRs are found in 80-90% of patients with generalized myasthenia gravis and in approximately 60% of those whose symptoms are restricted to the ocular muscles. 
Data from Indian patients has shown a median age of presentation at 48 years with a male preponderance of 2.7:1.  Seropositivity for AChRs is 59% in south Indian patients.  Clinical features of the disease in Indian population are not yet studied in detail.
There is a paucity of data regarding the disease in the state of Andhra Pradesh. We have studied the clinical and serological profile of patients presented to government general hospital, Guntur.
| Materials and Methods|| |
We studied the 13 cases and case records of 23 myasthenia gravis patients admitted to the government general hospital Guntur from September 2003 to April 2011. We have noted the clinical features and have done the repetitive motor nerve stimulation test, the neostigmine test, and the measurement of serum AChR antibodies.
Repetitive motor nerve stimulation test
For the repetitive motor nerve stimulation test, a train of electrical stimuli of four to 10 stimuli at rates of two to five per second were given to the facial nerve (in ocular involvement) and to the ulnar nerve (in upper limb weakness). The decrease in amplitude of motor potential after repeated stimulation was noted. A decrement of 10% or more denotes a failure of a proportion of the neuromuscular junctions. 
Neostigmine methylsulfate was injected intra-muscularly in a dose of 1.5 mg; atropine sulfate (0.8 mg) was given several minutes in advance to counteract muscarinic effects. We have observed for improvement of muscle function after 10, 15, and 20 min. Objective improvement in the form of decreased ptosis and increase in muscle power was taken as positive.
Serum AChR antibodies
Serum AChR antibodies were measured using radioimmunosorbent assay. Antibody level greater than 0.5 nmol/L was considered as a positive test.
Serum thyroid profile was done to assess the thyroid status. Computerized tomography (CT) scan of the chest was used to screen for thymic abnormalities.
| Results|| |
The median age of presentation was 40 years. Male to female ratio was 3:1. Males presented at an older age (median age 43) than females (median age 31.5). While 44.44% of the patients came with ptosis as their chief complaint, 72.22% had this clinical feature [Figure 1]. The other major complaint was lower limb weakness (38.89%) followed by easy fatigability (36.11%), diplopia (38.89%), and dysphagia (30.56%). Diurnal variation of weakness was noted only in 25.00%. Two of the patients had associated hypothyroidism. There were no significant comorbidities [Table 1].
CT of the chest showed three patients with thymic hyperplasia and four patients with thymoma. Repetitive nerve stimulation test showed decremental response in 86.36% of the cases. Neostigmine test was positive in all the cases [Figure 2].
| Discussion|| |
Our study shows that myasthenia gravis is more common in males. Weakness of the eye and its ancillary muscles seems to be the chief feature of this disease. Weakness of lower limbs is also manifested in many of the patients. Our study also shows a peculiar low percentage of diurnal variation of weakness. Seropositivity for AChR antibodies was 100% in ocular myasthenia gravis and 91% in the generalized form of the disease [Figure 3]. Serum AChR antibodies were elevated in 92.86% of patients with more median elevation in males (18) than in females (9.22) [Figure 4].
|Figure 3: Percentage of patients with acetylcholine receptor antibodies in serum +ve|
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The study was done on the basis of case records in a teaching hospital and hence there is more chance of a systematic and thorough record of the cases as each case comes under the purview of a hierarchy of professors, associates, assistants, and the postgraduate students. Interobserver bias is minimized with this setup. However, only those patients who have approached the institution have been studied and as such may not reflect the disease in the community.
Large-scale studies  outside India have shown that myasthenia gravis is more common in females. Our study concurs with the Indian studies which show a male to female ratio of 3:1.  This may be due to low reporting of female cases as they tend to be restricted to the households and may not have access to these institutions. Similar findings from developing countries like Bangladesh  support this theory.
Many of our patients came with ptosis as their complaint. This may be a true reflection of the manifestation of the disease or it may be due to the clinician bias. The text book  description of the disease emphasizes on drooping of the eyes and this might direct the physicians to myasthenia gravis. Patients with other symptoms may not be so easily identified.
Weakness of lower limbs has emerged as an important feature of the disease in our study. Most of the patients presented to our institution are agricultural laborers and day wage workers, in whom long hours of standing and walking may influence their presentation of their problems.
Levels of AChR antibodies are more in males than in females even though these higher levels in males did not show any significant relation to the severity of clinical symptoms. This might be due to the older onset of disease in males (43 years) when compared to the females (31.5 years). A study in 2008 from south India has shown that seropositive patients had higher age of onset.  The reason for the altered sex ratio in India and the higher values of AChR abs in male population and their significance is yet to be elucidated.
| Acknowledgements|| |
Department of Cardio thoracic Surgery, Government General Hospital, Guntur. Department of Radiology, Goverment General Hospital, Guntur.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]