Case 2:
We received a 37 days male baby who was referred by a surgeon for
medical management of multiple fractures and limb deformities discovered
at birth. It was an eventful pregnancy with normal prenatal tests. An
ultrasound done at 3 rd trimester revealed femoral bowing and
shortening. He was delivered through cesarean section at 37 weeks due to
uterine scar from a 32-years-old mother. He had a birth weight of 3000g
and a height of 40 cm. At birth, he presented with limb deformities and
painful mobility of lower limbs. He was admitted for an early neonatal
sepsis at day 2 of life with good improvement. He is the second child of
the family with no family history of consanguinity nor limb deformities.
At clinical presentation, anthropometric measures included a weight of
4000 g (-1 SDS), height of 45 cm (- 2 SDS) and head circumference of 35
cm (+ 0.5 SDS). The child presented with reduced mobility, frontal
bossing, blue sclerae, bowed legs and shortened limbs. Limbs X-rays
showed multiple incomplete diaphyseal fractures of long bones and curved
bones (Figure 4 ). The patient also presented an undisplaced
sternal fracture. Genetic tests are not yet available in our country.
According to clinical and radiographic findings, Osteogenesis Imperfecta
was the more likely diagnosis of this bone fragility. We suggested OI
type II or III as diagnosis due to antenatal deformities and multiple
fractures at birth. For management of this condition, the child
performed orthopedic treatment with many casts for recent fractures.
Bone callous was obtained after 8 weeks with pain improvement. He also
received oral Vitamin D supplements. Bisphosphonates are planned but not
yet available for this child.
DISCUSSION:
Osteogenesis Imperfecta is a common cause of bone fragility in children.
Clinical diagnosis is usually based on skeletal signs as in our patient.
This genetic disorder can also present with extraskeletal signs such as
respiratory distress, cardiovascular abnormalities, dentinogenesisi
Imperfecta, blue sclerae, hearing impairment and vascular
fragility[6][7]. Genetic tests can confirm the diagnosis but
molecular abnormalities of type 1 collagen (COL1A1 and COL1A2 )
are only reported in 85% of patients[2]. Antenatal or neonatal
onset of this condition as in our patient suggests a severe form with
high mortality rate. These forms can be suspected on antenatal
ultrasound (bone deformity, fracture, bone shortening)[6]. These
features were reported during antenatal ultrasound of our second
patient. This highlights importance of ultrasound for antenatal
diagnosis of this condition.
Sillence classification distinguishes four types of OI based on
clinical phenotypes and disease severity[3]. Recently,Glorieux et al. added three types with the same phenotype of OI
previously described but not related to type 1 collagen mutations
[4]. Types II and III are the most severe forms with antenatal or
neonatal onset. Our patients probably had Type III OI due to early onset
of bone fractures and deformities. The prognosis is reserved in neonatal
forms due to intracranial hemorrhage or respiratory insufficiency
following chest deformity[6). Respiratory distress of the first
patient at admission caused fear of respiratory insufficiency or
associated cardiovascular malformation. A normal cardiac ultrasound
ruled out these comorbidities that are life-threatening in severe forms.
In addition, transfontanellar ultrasound eliminated intracranial
hemorrhage.
The management of OI is multidisciplinary including surgical and medical
treatment of bone fragility [8]. Orthopedic management or surgical
treatment of fractures and bone deformities is essential during
follow-up [6]. Physiotherapy helps to maintain mobility, maintain
muscle mass and improve motor skills. Bisphosphonates are considered as
first line medical treatment for OI [9]. Benefits of this treatment
include reduced pain, increased bone mass density and reduced incidence
of fractures[10]. The psychosocial support of families is necessary.
In our country, management of these patients remain difficult due to low
socio-economic level.
CONCLUSION:
Osteogenesis Imperfecta is a rare inherited disease leading to abnormal
bone fragility. Early forms are reported to be severe. Therefore,
caregivers should be aware of this condition when bone deformities and
fractures are observed in a neonate. Genetic counselling and prenatal
diagnosis should be considered in these families.
Authorship: All the authors managed these patients, searched
literature and revised the manuscript. MBRC and MANNY designed the
manuscript.