INTRODUCTION:

Anencephaly represents 40% of neural tube malformations, which is the second leading cause of nervous system abnormalities after spina bifida. The diagnosis is completed by the 1st trimester with an ultrasound between the 11^th and 14^th week. The causative factor of this type of nervous system abnormalities is not well known. One of the previous studies from the literature has revealed its causes are multifactorial such as genetic, infectious, nutritional, or environmental factors, and other maternal conditions.¹ Current evidence suggests that it correlates with low folate level, low socioeconomic status, ethnicity, and geographical distribution. There were some articles suggesting the association between congenital abnormalities and febrile illness in the early three months of the pregnancy.

CASE REPORT:

A 33-year-old lady in her third pregnancy presented with per vagina spotting to Emergency Department (ED). Her periods were irregular since menarche. The examining doctor did not convince them of her pregnancy as her urine pregnancy test was negative in ED although she informed she tested her urine test was positive at home. She was confirmed pregnant with a serum β Human Chorionic Gonadotrophin test one week later at the clinic. The ultrasound dating scan at that time was 10 weeks and 2 days gestation. She was not satisfied with this delayed incident as she believed she did not get the chance to consume the Folic acid tablets as early as possible. She is a known case of hyperthyroidism under carbimazole tablet for a year, further, the medication was changed to propylthiouracil tablet. She had two previous normal alive-term delivery. The repeated ultrasound scan was done at next month and the doctor could not measure the biparietal diameter and became suspicious of anencephaly. It was confirmed anencephaly with formal ultrasound from the radiologist who reported no definite brain parenchyma noted, the head was small in size. It was a great shock for her and her family. The Obstetrician informed me about the condition and its prognosis. She was offered two options: termination or continuation of pregnancy. After thinking long and hard, the couple decided to continue the pregnancy. Her antenatal care was uneventful until 26 weeks when she was diagnosed with Gestational Diabetes Mellitus (GDM). Her GDM was well-controlled throughout the pregnancy. Her consecutive ultrasound examinations showed a normal amniotic fluid index with normal fatal growth. However, she developed spontaneous labor pain at 38 weeks of gestation and delivered vaginally an anomalous male baby of 2.84 kg. The baby was crying for a weak and was admitted to Special Care Baby Unit. The paediatrician who attended labour found out that the baby had anencephaly as well as meningomyelocele (Fig. 1). The baby passed away after six days. We reassured the parents that the recurrent rate is about 2%. We highlighted the role of folic acid in her next pregnancy to prevent the occurrence which she agreed. She still believed if she had taken the Folic acid tablet in early pregnancy, the baby might not have this anomaly. She was very traumatized and anxious about going for new pregnancy again; in fact, recently she had a healthy full-term delivery with a healthy baby.

DISCUSSION:

Anencephaly is a congenital and lethal malformation of the central nervous system. The exact etiologic anencephaly is unknown and undetermined, but it results from the failure of normal primary neurulation, an embryologic process that is normally completed in humans by about day 26-28 post-conception. In this process, there is a failure of normal closure of the anterior neuropore and it ends up in anencephaly. Regarding its developmental anatomy, it is classically subdivided into two forms: holo-anencephaly, which is a complete absence of the forebrain and cranium, and mero-anencephaly, which is the cranium and the brain are present in rudimentary form.²

One of the supporting literature studies demonstrates the case with a complete absence of fore brain and cranium that indicates holo-anencephaly. Nanagas³ in their book has classified 5 types of anencephaly, depending on the extent of anatomical involvement,among these types, the type1 is anencephalic acrania, the commonest type that the clinicians realized and recognized more on the topic, and Acrania- Exencephaly- Anencephaly Sequence (AEAS), is accepted by many authors. This concept was introduced as early as the 1950s. Observed study in the literature reveals that according to AEAS, the cerebral tissue that is not protected by the meninges, cranial bones, and the skin is gradually destroyed due to exposure to the harmful effect of amniotic fluid that is increased urea concentration in the amniotic fluid and mechanical injuries that is a risk of friction with the uterine wall, placenta, and fetal parts. This leads to exencephaly and then into anencephaly.⁴

Another piece of literature evidence that the male and female ratio is 2:3, which demonstrated more skewing toward females. The maternal age shown in the study is ranging from 18 to 33 years. The gestational age at delivery ranges from 28 to 36 weeks.⁵ Ultrasound, especially anomaly scan or detailed scan, plays an essential role as it is non-invasive. Levi S., study a comprehensive review of the foetus to rule out the structural anomalies. Anencephaly is detected prenatally by first and second-trimester ultrasound at present time reports, the average age of diagnosis of 22 weeks, varying between the 20th and 30th week of amenorrhoea. First and second-trimester ultrasound at present time.⁶

The detection rate for anencephaly is 98%. The Eurofetus study also confirmed in its findings that CNS anomalies had the highest detection rates, which are 88.3%.⁶ Mickey Mouse sign (First Trimester), Frog eyes sign (Second Trimester), and the latest finding of Beret sign are USS findings for anencephaly. The Mickey Mouse sign is typical for exencephaly. A literature study has revealed that a normal amount of brain tissue is visible in the Coronal Plane of the fetus, which causes the appearance of the Mickey Mouse. The analysed animal study from the literature evidence frog eye sign is caused by a lack of recognizable brain tissue above the level of fetal orbits due to the absence of the forebrain and cerebrum, which is seen with a significant increase in the echogenicity of the amniotic fluid. Studies evidence that the Beret sign is a new sign observed in the acrania stage best seen in the midsagittal and frontal section that is observed between the described membrane and the brain structures, which is a thin anechoic space corresponding to cerebrospinal fluid.⁷

The main differential diagnoses are severe microcephaly and osteogenesis imperfecta. In the case of severe microcephaly, the fatal head may be so small that it can be confused with anencephaly. However, in contrast to anencephaly, the echogenic calvarium will be seen surrounding the fatal head. In the case of severe osteogenesis imperfecta and congenital hypophosphatasia (type A, perinatal), which results in decreased ossification of the calvarium. In these cases, the cranium is often deformed, difficult to differentiate from acrania, and ultrasound may not be a reliable diagnostic tool. A family history of fractures may be helpful.

In general, termination of pregnancy is offered to patients when anencephaly is detected as it is a lethal anomaly. Many laws permit termination of pregnancy on this indication or on the effects of pregnancy and prospects of delivery on a woman's physical or mental health. The pregnant mother decides to continue her pregnancy, repetitive antenatal care is offered after thorough counselling highlighting the pregnancy outcome, which is seen in the current case study. Normal vaginal delivery is a preferred mode of delivery. The neonates with anencephaly should be given palliative care and family members should be offered support. Bereavement counselling for the couple and close monitoring in future pregnancy with high dose folic acid are recommended in future management. It is important to recognize the parents with intense grief and depression to avoid unnecessary adverse psychological outcomes.

There is no treatment for anencephaly. Previous literature study evidences the importance of preventive measures such as, fortification of essential foods or supplementation of high-dose Folic acid (4 mg) in women who are bearing child age group and in the first month of pregnancy.⁸

The literature so far confirmed fortification program prevented about a 28% reduction in the USA.⁹

It the estimated that the empiric risk of recurrence is about 2 – 2.2%. After the birth of 2 affected babies, the incidence of congenital defects again is 9%.¹⁰

Fig. 1 New-born baby with anencephaly and meningomyelocele

CONCLUSION:

Anencephaly is a lethal malformation. Early recognition of the condition will help the couple to tackle this dilemma faster and better in an ample period. They can accommodate the situation in due time to reach a decision of termination that would be easier and safer if they proceed in early gestation. The patient in the current case study who prefer to continue her pregnancy were provided with counselling and moral support to the family to avoid adverse psychological outcome can be organized by a multidisciplinary team, which include an obstetrician, paediatrician, social worker, and nurse. In the current event, the patent was lacking treatment, prevention, and awareness of the condition is the main issue. This case study insights into the importance to extend the bereavement support or perinatal palliative care in the management as the adverse psychological effect like guilt, intense grief, undue worries about a future pregnancy, and shame surfaced after the incident. Good communication, empathic support, and efficient counselling will be beneficial to settle these challenges.

ACKNOWLEDGEMENT:

I would like to thank our University Malaysia Sarawak to support our publication.

CONSENT:

Written informed consent was obtained from the patient for publication of this case report and all accompanying images.

CONFLICTS OF INTEREST:

The authors declare that there was no potential conflict of interest relevant to this article was reported.

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Received on 13.02.2022 Modified on 19.03.2022

Research J. Pharm. and Tech. 2022; 15(5):2097-2099.

DOI: 10.52711/0974-360X.2022.00347