Bosma Arhinia Microphthalmia Syndrome - An Overview

Introduction:

BAMS (Bosma arhinia microphthalmia syndrome) was discovered in 1981. It is a rare genetic disorder that can be identified due to the absence of a nose or the presence of abnormalities in the eyes and hormones. In most of the cases, brain abnormalities and intellectual abnormalities are rare.

What Is Bosma Arhinia Microphthalmia Syndrome?

It is a genetic disorder that can be characterized by the absence of the nose, abnormalities related to the eyes, and the development of puberty.

What Are the Causes of Bosma Arhinia Microphthalmia Syndrome?

• The most common causes of the disorder include mutations of the gene SMCHD1. This gene-silencing effect influences the nose, eyes, and craniofacial structure development.

• Studies are still being carried out to know the mechanism of the pathway in which the mutations in the gene affect the body's functioning.

• This mutation in the gene can lead to gene silencing, which does not show the expression of the gene resulting in defective structure development.

• Gonadotropin-releasing hormone influences nasal development, consequently controlling reproductive hormone production.

• A decrease in gonadotropin levels can lead to hypoplasia of the genital organs in certain individuals.

What Is the Incidence of Bosma Arhinia Microphthalmia Syndrome?

The prevalence of the disease is not clear between males and females. Despite the absence of a nose, the individual suffering from this condition does not show any deformities in the larynx and can breathe normally with the help of their mouth. Due to the lower number of cases, the incidence of the disease is unknown.

What Are the Symptoms of Bosma Arhinia Microphthalmia Syndrome?

• Ophthalmic and Nasal Abnormalities: Abnormalities of eyes and nose.

• Puberty Changes: Disturbance in the development of puberty.

• Arhinia: absence of nose leading to airway obstruction that is present right from birth. It is associated with other facial abnormalities, especially the eyes and palate.

• Partial Aplasia of the Nose: Absence of a few nasal structures occurring from birth results in partial aplasia.

• Neurological Changes: Abnormalities in the brain structure.

• Change in Sense: Absence of olfactory bulb.

• Hyposmia: A decreased sensation of smell or altered ability to identify different smells through the nose.

• Anosmia: Complete loss of smell, which is a temporary or permanent condition due to irritation in the mucus membrane of the nose, nasal obstructions, and congenital defects.

• Ageusia: A condition that leads to loss of taste function which can occur due to many pathological conditions.

• Bilateral Microphthalmia: An abnormality that shows the presence of small eyeballs in both eyes, which occurs before birth. It may or may not lead to vision loss.

• Anophthalmia: Congenital defect where the baby is born with a single or absence of both eyes.

• Loss of Visual Acuity: Impairment of vision where the eyes cannot clearly see the object due to loss of visual field.

• Social Dissatisfaction: Constant loss of satisfaction anytime individuals interact socially.

• Emotional Distress: Highly emotional individuals burden themselves with certain memories or patterns of situations leading to emotional distress.

• Craniofacial Defects: Defects of the face and skull.

• High Arched Palate: Palate which is narrow and has high development defects during birth.

• Naso-Lacrimal Duct Stenosis: Blockage of the duct through which the tears are produced when proper drainage does not occur; irritation and itching can occur.

• Small Maxilla: Presence of upper jaw smaller in size.

• Reproductive Problems: Decreased efficiency of the reproductive system.

• Genital Problems: Abnormal genital development.

• Osteoporosis: Condition of the bone where the mineral density and bone mass are decreased, leading to a high risk of fractures.

What Is the Diagnosis of Bosma Arhinia Microphthalmia Syndrome?

• CT Scan: Computer tomography (CT) digitally visualizes the internal organs of the body. It helps to access the olfactory and ophthalmic regions of the body. The absence of sinuses and underdeveloped nasal bones can be seen in the radiographic images.

• MRI: Magnetic resonance imaging (MRI) technique is an advanced radiographic technology as compared to CT scan, which helps in better visualization and understanding to propose treatment.

• Laboratory Investigations: Hormonal deficiencies should be checked to understand the underlying cause of the condition. As mutations of genes causing BAMS decrease the levels of gonadotropin hormone, it should be checked.

What Is the Treatment of Bosma Arhinia Microphthalmia Syndrome?

• As the absence of a nose characterizes it, it can be diagnosed easily, and early recognition is critical.

• Management of this genetic condition is not specific, and investigations of nose, eyes, heart, and reproductive defects should be evaluated, which are then followed up by surgical treatment.

• Reconstruction of anatomy or structural defects can be done by plastic surgery after the patient has reached adulthood.

• A nasal reconstruction procedure can help in repairing the deformities that occurred genetically, keeping in mind to follow a well-established surgical technique.

• Construction has a special position in plastic surgery as it has a three-dimensional nasal surface along with differences in the overlying skin thickness.

• Then anatomy of the nose is thoroughly evaluated, and opted for a proper procedure, and the surgery is carried out.

• Bony defects, along with soft tissue defects of the nose, are reconstructed.

• Reconstruction requires graft from the same individual or different individuals, which can be obtained from the cartilage of the ear.

• A flap can also be adapted for the reconstruction of the nostril, which gets its blood supply from the blood vessels of the eyebrow.

• Grafts are collected from areas that can compromise the aesthetics of the individual to a minor extent.

• Examination of the genital organs is necessary, particularly in female patients, and should be treated symptomatically to improve the capacity of reproduction.

• Vitamin supplements should also be advised to prevent osteoporosis.

Follow Up:

Abnormalities associated with the condition should be regularly followed up depending on the clinical presentation. It is an essential part of management.

Conclusion:

It is a rare condition identified in very few individuals worldwide. Various organs get damaged due to this condition. Clinical features such as the absence of a nose, depressed mid-face area, upper jaw hypoplasia, high-arched palate, and absence of olfactory bulbs help in clearly diagnosing the condition. Studies have been carried out to avoid confusion in diagnosis and to approach the case clearly, and the physicians are capable enough to treat symptoms of the condition. It also becomes the individual's responsibility to consult a healthcare physician upon noticing such symptoms.