LI Shenmei,LI Yuan,TANG Meiqiong,DAI Yunyun,GAO Yan

(School of Nursing Guilin Medical University,Guilin,Guangxi,541004)

ABSTRACT: Autosomal-dominant centronuclear myopathy is a rare hereditary disease in adolescents,mainly involving the distal muscles of the lower extremity. It is extremely rare in pregnancy. This study presented a case of a woman by successful IVF and caesarean delivery without complications in autosomal dominant centronuclear myopathy. This report also reviewed the clinical spectrum of CNM and its management,which resulted in the delivery of a healthy infant. It is important that the clinician has a clear understanding of the clinical spectrum of CNM,the available methods for perinatal diagnosis,and optimal antenatal care. A multidisciplinary team approach is emphasized,with specific reference to the method of analgesia and anesthesia during labor and route of delivery.

KEY WORDS: autosomal dominant centronuclear myopathy; pregnancy woman; vitro fertilization and embryo transfer; caesarean delivery

Introduction

Autosomal dominant centronuclear myopathy is a rare hereditary disease in adolescents,mainly involving the distal muscles of the lower extremity[1-2]. With the development of the disease,the distal and proximal muscles of the four-limb,the facial muscles and the ophthalmic muscles can be involved,and there are varying degrees of muscular atrophy of the body. It is extremely rare in pregnancy. However,it may adversely affect pregnancy,and pregnancy may exacerbate the natural progress of the condition .A search of Medline from January 1966 to August 2019 was carried out,in the English language,with a key word search using “Autosomal dominant hereditary central myopathy”,“embryo transfer”,“cesarean section”,“pregnancy”,“antenatal diagnosis” and “anesthesia.” We report the first case of the success of cesarean section woman ( by IVF-ET )who got autosomal dominant hereditary central myopathy.

Case presentation

A 27-year-old woman who had suffered autosomal-dominant centronuclear myopathy and by her first in vitro fertilization and embryo transfer. The patient,who suffered from systemic weakness and double eyelids drooping for more than 20 years,was diagnosed with autosomal dominant central myopathy in 2013. After six months of taking the medicine as ordered by the doctor,she stopped on her own and without any further treatment. In 2014,her first five-month-old fetus was diagnosed with central myopathy through amniocentesis. In September 2017,she underwent a third generation of in vitro fertilization and embryo transfer. She had no history of viral infection,ototoxicity,radiation exposure,and fetal care. She had regular birth tests,and the results were normal (including glucose tolerance tests,thalassemia screening,birth screening system color Doppler sonography and amniocentesis).

On May 29,2018,she had 38 weeks and 6 days of gestation,myasthenia for more than 20 years,asked to be hospitalized to give birth. Four parts palpation: vertical production type had entered the basin. Vaginal examination: the cervix was soft,the uterus was not open,and the membranes were not broken,pre-exposure s-2. Auxiliary examination results: B ultrasound results were intrauterine single live pregnancy,amniotic fluid index 219 mm. Uterine height was 34 cm,abdominal circumference 90 cm,fetal heart sound normal. The muscle strength of upper limb was 4 grade,iliopsoas muscle,quadriceps femoris muscle strength 3 grade,ankle flexion and extensor force 4 grade,muscle tension was low. The result of the symmetry of tendon reflex was decreased and deep shallow sensory examination was normal. The patient and their families were informed with the potential risks of vaginal delivery and cesarean section. They agreed to cesarean section. On the one hand,doctors and nurses had actively prepared for surgery (blood transfusion group,hemostatic drugs,liver and kidney function tests,Dantrolene to prevent malignant hyperthermia after anaesthesia); On the other hand,doctors and nurses had actively monitored fetal heart sounds and invited specialists form Departments of Anesthesiology,Neurology,ICU,Cardiovascular Department,Respiratory Department,and Pediatric Department. A multi-departmental cooperation was performed to ensure successful delivery.

At 13:00 on May 30,2018,under spinal anesthesia,we performed lower segment cesarean section with Blynch suture and uterine artery ascending branch ligation. During the operation,we injected Carboprost Tromethamine 1 branch intramuscularly to promote uterine contraction,during the operation,the patient's bleeding volume was about 400 mL. The operation went smoothly for about 2 hours. A female infant was delivered with Apgars score of 9 at 1 and 10 at 5 minutes,weighing 2.88 kg. The newborn did not show any signs of weakness,hypotonia,respiratory difficulties,or facial,palatal,or mandibular abnormalities. Owing to surgical stress might aggravate muscle weakness,especially respiratory muscle,and cause dyspnea,and post-anesthetic paralysis,respiratory paralysis and malignant hyperthermia,the patients was transferred to ICU for further treatment. After transferring to ICU,her vital signs were stable,conscious. Physical examination: lower extremity weakness with mild edema,muscle strength of both upper limbs grade 4,cardiopulmonary function normal,blood gas analysis and blood biochemical results were normal,vaginal bleeding 150ml,the right abdominal drainage tube drained dark red liquid 220ml. The patient was given nutritional myocardium,gastric medicine and blood clotting factor supplement.

The patient had no difficulty breathing and was transferred to obstetrical ward for treatment at 9 o'clock on May 31. Treatment programs included: ①intravenous drip of antibiotics for three days to prevent infection,②monitoring of vital signs,③fluid rehydration,promotion of uterine contraction,④recovery of gastrointestinal function and prevention of deep venous thrombosis. On the second day after operation,the patient could eat liquid food and get out of bed. during 7 days,the patient`s vital signs were stable,the incision had no redness and swelling,the uterus contracted well,the amount of lochia was less,and there was no peculiar smell. On the seventh day after operation,her abdominal wound was disconnected intermittently and informed of the matters needing attention,and the patient was discharged from hospital.

After three months follow-up,the patient recovered well. The infant weighed 6.2 kg and was in normal physical development. The infant was artificially fed with 140ml of milk each time.

Conclusion

Centronuclear myopathyis an inherited neuromuscular disorder characterized by clinical features of a congenital myopathy and centrally placed nuclei on muscle biopsy. It has genetic heterogeneity,it can be X-linked recessive inheritance,autosomal dominant inheritance and autosomal recessive inheritance[3-5]. There were fewer cases of congenital myopathy associated with pregnancy,but both emphasized that patients with respiratory muscle involvement had inadequate ventilation and were prone to respiratory failure and respiratory infections. Due to low maternal partial pressure of oxygen,fetal intrauterine hypoxia and fetal growth restriction,as well as the rate of premature delivery and caesarean section increased. At the same time,pregnancy is at risk of exacerbating the condition.

One patient with central nucleus myopathy is representative for the following reasons: first,the disease is a congenital myopathy; for women,changes in pregnancy and childbirth may aggravate the severity of the disease[6-8]. At the same time,the progression of the disease may result in a significant increase in the risk of pregnancy and childbirth compared with the general population. Second,the patient was diagnosed as autosomal dominant centronuclear myopathy,which is higher than other genetic types,so genetic counseling and prenatal diagnosis will help to prevent and control the risk of offspring,then after the first pregnancy failed[6,9],the patient chose embryo transfer. Third,during pregnancy,it is required to pay attention to active prevention and control of pulmonary infection,monitoring of respiratory function,prevention and control of possible respiratory failure and secondary pulmonary heart failure,and preventive use of non-invasive positive pressure ventilation,if necessary,It is beneficial to improve restrictive ventilation disorder. If the fetus matures,give birth early in time to reduce the threat of respiratory failure to the mother and fetus. The mode of delivery shall be decided by the obstetrics and gynecologist and the anesthesiologist.

In a word,for this similar case,if the patient's respiratory function is close to normal before pregnancy,the pregnancy and delivery can be successful with the close cooperation of cardiovascular department,respiratory department,anesthesiology and obstetrics department and so on. In order to prevent and control perinatal complications in patients with this disease,it is necessary to enhance the awareness and vigilance of the disease and its maternal risk in the relevant disciplines,so as to take effective measures to prevent and control the risk of perinatal complications in pregnant women with this disease.

Acknowledgment

All persons who have made substantial contributions to the work reported in the manuscript.

Disclosure of Conflicts of Interest

No potential conflict of interest was reported by the authors.