Neuromuscular

Home, Search, Index, Links, Pathology, Molecules, Syndromes,
Muscle, NMJ, Nerve, Spinal, Ataxia, Antibody & Biopsy, Patient Info

Differential Diagnosis of Myasthenia Gravis

Fatigue (Ptosis): Familial MG

AUTOIMMUNE MG: Neonatal & Juvenile Forms

CHILDHOOD MYASTHENIA GRAVIS: TYPES
Neonatal
Transient
Recurrent
Arthrogryposis
Fetal AChR
Inactivation
Congenital Familial
Infantile
Acquired
Child
Maternal MG + + + - - -
Onset age 0 to 3 days
post natal
Congenital Congenital Birth Birth
to 1 year
> 1 year
More in Orientals
Weakness General General Face, Bulbar
Respiratory
Ocular
± General
Respiratory
General
Ocular
± General
Time course Remission
1 to 6 weeks
Static Improve
  over years
Fixed
  weakness
Fatal early, or
Improve > 2 years
Improve
  over years
Family history ± Other sibs
Mother
  Untreated
Other sibs
Mother
  Untreated
Other sibs
Mother
  Untreated
Often Usual Rare
Anti-AChR antibodies Most + vs
Fetal AChR
+ vs
Fetal AChR
- - 50% to 90%
More in Orientals



Myasthenia gravis: Neonatal Transient

Fetal acetylcholine receptor inactivation syndrome 3


Recurrent Congenital Arthrogryposis 1

Myasthenia gravis: Autoimmune, Childhood 2

Myasthenia Gravis: History





P. S., aet. thirty-seven, a baker, applied for treatment at the out-patient department at the Victoria Park Hospital, on Friday, February 11th, 1887. From statements he then made, and from facts obtained from his widow on a subsequent occasion, the history of the case is briefly as follows :

He was a married man with seven healthy children. He had always followed his present occupation, that of a baker; he had never suffered from any venereal complaint, and had enjoyed perfect health until his present illness began, six months ago. At that time he was kept from his work by a very severe attack of diarrhoea, which lasted a fortnight, but did not necessitate his staying in bed. Ever since this attack he had suffered from an ill-defined feeling of weakness, becoming gradually more severe, but with occasional remissions. This progressive weakness had been noticed more in the arms than in the legs, and had quite early in the illness been observed in the act of mastication. Throughout there had been wasting of the body generally, and at no time had the patient been well enough to resume his work. During the last month the weakness had been much more marked, and it was within this time that the symptoms had been noticed which led him to seek advice at the hospital.

There had been difficulty of articulation, so that the patient could not make himself clearly understood. At the same time he had found trouble in deglutition-a trouble that was more marked with solid than with liquid food. These symptoms were but slight in the morning, but became more evident as the day advanced. There had been copious secretion of frothy mucus, which he found very difficult to spit out, and which he feared sometimes would choke him. Within the last fortnight he had two severe attacks of shortness of breath, which gave great alarm to his friends.

He walked into the out-patient room assisted by a friend and required help in undressing. He could however stand and walk a little unaided, but said that he often fell, and was quite unable to walk downstairs alone. When sitting he could not cross one leg over the other without lifting it with his hands. He spoke slowly and indistinctly, reminding one of a patient suffering front tonsillitis. The special difficulty of articulation was not investigated except that he had more difficulty in pronouncing hard " c " than other consonants. There was no nasal twang to his voice, and his soft palate was seen to move well and equally. His mouth was constantly held slightly open, but there was no dribbling of saliva, on the contrary what saliva and mucus collected in the mouth was cleared away with the fingers after futile attempts to expectorate it. There was loss of power in the lower facial muscles, so that the naso-labial fold was obliterated on either side, causing a vacant expression. He was unable to whistle or blow out a light. The loss of power was quite equal on the two sides, and did not affect the upper facial muscles at all, the patient being able to screw his eyes up firmly. The only evidence of any weakness of the muscles of the tongue was a difficulty in starting its protrusion; when protruded it could be moved in any direction, though slowly. The masseters were decidedly weak; the man stating that he was obliged to help mastication by pushing up his jaw with his hand, and complaining that he could not hold his pipe in his mouth either with his lips or his teeth without similar aid. The difficulty in swallowing of which he complained was well shown on his attempting to drink some water. The patient having filled his mouth, threw his head back, when some of the water seemed to get into his oesophagus, but almost at once he choked, and holding his head forward most of it ran from his lips. The laryngoscope showed his vocal cords to move well, whilst the ease with which the examination was made seemed to show some impairment of sensibility of the fauces.

Diplopia had sometimes been noticed by the patient, though at the time of his visit there was none; the pupils, motor oculi muscles and fundus of the eye were all normal.

The muscles of the trunk and extremities were ill-developed and flabby, but there was no obvious wasting of any group of muscles. The grasp was decidedly feeble, but equal on the two sides.

The wrist, elbow and knee jerks were brisk, a little above the average. In the right ankle an attempt to produce clonus resulted in four or five contractions; there was no response on the left side. The cremasteric and plantar reflexes were present and equal; the abdominal and epigastric absent. His memory and other mental functions appeared normal. Throughout his illness there had been perfect control over his bladder and rectum. Physical examination of his chest showed nothing abnormal with the heart or lungs. On first lying down for examination the patient complained of difficulty of breathing; no change in the rate of respiration or general condition could be observed, and the sensation soon passed off.

The man became an in-patient on Februray 12th, 1887. His condition did not attract special attention until the evening of the 13th. At that time he was attacked with sudden and urgent dyspnoea. The resident medical officer who was called to see him considered his condition to be due to paralysis of the intercostals, the expansion of his chest being carried on by the accessory muscles of respiration. He was becoming rapidly cyanosed, so that artificial respiration was tried with good result. The improvement was only temporary, and the proceeding had to be resorted to again and again. The following note was made of his condition in the intervals of the attacks: "His tongue is protruded straight. There are no ocular paralyses; pupils react readily and equally. He speaks clearly. The mouth is not drawn to one side. He cannot swallow his saliva, which collects about the fauces and is spat out with great difficulty, apparently from weakness of the muscles of the cheeks and tongue. Respiration is short and jerky; chest is full of large moist rales. Nothing can be felt at the back of the pharynx. There is no obstruction in the larynx to the entry of air. His hands are cold, and when an attack of dyspnoea is coming on he beats his chest and throws his limbs about in great distress, and asks to have artificial respiration performed. His mind is quite clear."

Subsequently the attacks became more frequent and severe, especially with regard to the urgency of the feeling which the patient described as an inability " to expand bis lungs." Artificial respiration was repeatedly performed and for long periods, but this was at last ineffectual and the patient died a few hours after the beginning of the attack.

Return to Myasthenic syndromes
Return to Neuromuscular home page

References
1. Am J Med Genet 2000; 92:1-6
2. Neuromuscular Disorders 2011; Online Sept, J Neurol 2017 Mar 31
3. Neurol Neuroimmunol Neuroinflamm 2015;2:e57
4. Arch Neurol 1988;45:185-187

10/7/2019