Rickets in Children: Symptoms, Causes and Treatment
Contents
- How Vitamin D Affects The Body?
- Bones Growth and Development a Complete Guide
- Deficiency of Vitamin D
- Hypocalcemia
- Hypophosphatemia
- Bone Resorption
- Delayed Ossification
- Types of Rickets in Children
- 1- Vitamin D dependent rickets
- 2- Defect in alpha-1 hydroxylase kidney like is osteodystrophy.
- 3- Vitamin D deficiency rickets
- 4- Vitamin D resistant rickets
- Classic Signs of Rickets in Children
- 1- Head
- 2- Legs
- 3- Spine
- 4- Thorax
- 5- Teeth
- How to Diagnose the Rickets in Children?
- Xrays
- Blood tests
- Treatment of Rickets
- Sources
Rickets in children is usually caused by a lack of vitamin D, calcium, or phosphate. Vitamin D comes from food and from sunlight on the skin. In adults, softening of the bones from the same causes is called Osteomalacia, while in children it is known as rickets.
Boys and girls are equally affected. Babies of mothers with low vitamin D, and babies who are exclusively breastfed without a vitamin D supplement, are at higher risk. Rickets is a failure to mineralize the growing ends of the bones, so bones become soft and weak and can bend under the body's weight.
Bones become soft and children may have bone pain, muscle weakness, or cramps. According to MedlinePlus, risk rises with limited sun exposure, avoiding milk products, and some kidney, liver, and digestive disorders.
Breast milk contains little vitamin D. That is why breastfed babies are usually given a daily vitamin D supplement of 400 IU from birth; ask your pediatrician what your child needs.
How Vitamin D Affects The Body?
Vitamin D is required to maintain the blood levels of calcium and phosphorus. It is also involved in bone growth and bone health. It maintains calcium and phosphorus levels in three ways:
- Increases the absorption of calcium and phosphorus from the intestine
- Works with parathyroid hormone to release calcium from bone when blood levels are low
- Increases the reabsorption of calcium and phosphorus in the kidneys
Vitamin D comes in two main forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). There is no vitamin D1 in use. Neither form is active until the body converts it, as explained below.
Bones Growth and Development a Complete Guide
Our skin contains 7-dehydrocholesterol, which is converted to vitamin D3 when ultraviolet rays fall on the skin. Vitamin D3 travels in the blood bound to vitamin D-binding protein and is carried to the liver.
In the liver, it is converted into 25-hydroxyvitamin D. In the kidney, the enzyme 1-alpha-hydroxylase converts this into 1,25-dihydroxyvitamin D (calcitriol). Calcitriol is the active form of vitamin D and works like a steroid hormone.
Deficiency of Vitamin D
As we have discussed, vitamin D maintains the level of calcium and phosphorus. Its deficiency reduces their absorption and causes the following.
Hypocalcemia
Less calcium and phosphorus are absorbed from the intestine, which can lead to hypocalcemia (low blood calcium).
To keep blood calcium normal, the body releases more calcium from the bones.
Hypophosphatemia
With vitamin D deficiency, the body loses more phosphorus in the urine, which leads to hypophosphatemia (low blood phosphate).
Bone Resorption
Because more calcium is taken from the bones, the bones become weak and bone density falls.
Delayed Ossification
In infants and children, the growing ends of the bones fail to mineralize. The growth plate cartilage keeps building up without hardening into bone, so bone formation is delayed.
Types of Rickets in Children
There are four main types of rickets.
1- Vitamin D dependent rickets
Vitamin D-dependent rickets is a rare inherited condition. In type 1, a gene change reduces the kidney enzyme 1-alpha-hydroxylase, so the body cannot make enough active vitamin D. In type 2, a change in the vitamin D receptor gene makes the body resistant to active vitamin D, even when levels are normal. Both types usually show up in infancy with poor growth and rickets that does not respond to standard vitamin D.
2- Defect in alpha-1 hydroxylase kidney like is osteodystrophy.
The enzyme 1-alpha-hydroxylase is found mainly in the kidney, and also in some other cells. It converts 25-hydroxyvitamin D into active 1,25-dihydroxyvitamin D. Chronic kidney disease can reduce this conversion, causing renal osteodystrophy, a bone disease that can look like rickets in children.
3- Vitamin D deficiency rickets
This is the most common type. It is caused by too little vitamin D from food or sunlight, sometimes together with too little calcium.
4- Vitamin D resistant rickets
This type, now called X-linked hypophosphatemic rickets, is an inherited X-linked dominant disorder that affects both boys and girls. The kidneys waste phosphate, and the body does not make enough active vitamin D. It is treated with phosphate and active vitamin D, or newer targeted medicines, by a specialist.
Classic Signs of Rickets in Children
Rickets in children has some classic signs that help doctors recognize it. It occurs most often between 6 months and 2 years of age. It mostly affects fast-growing bones, with widening at the wrists, knees, and ankles. Common features of rickets in children are:
1- Head
- Frontal bossing of head
- Delayed closure of the anterior fontanelle (soft spot)
- Soft, thin skull bones at the back of the head that feel like a ping-pong ball when pressed (craniotabes)
- The square shape of the head
2- Legs
Image Source
- Bowed legs (or knock knees)
- Greenstick fractures may occur.
- Ends of long bones are flaring and rough.
- Hypotonia (low muscle tone)
- Widening of wrist joint, ankles, knees
3- Spine
- Defective spinal growth can cause kyphosis (hump-shaped back) and
- scoliosis (sideways curve), which is sometimes confused with Sclerosis, a different condition
4- Thorax
Their chest may show a rachitic rosary (bumps where the ribs join the cartilage), pigeon chest deformity, and Harrison sulcus (a groove along the lower ribs where the diaphragm attaches).
5- Teeth
They also may have delayed eruption of baby teeth, delayed or impaired growth of permanent teeth, defective enamel, and cavities.
How to Diagnose the Rickets in Children?
Doctors suspect rickets from the child's signs and confirm it with tests. Findings include:
Xrays
Widening of the wrist joint. There is fraying, flaring, and cupping of the ends of long bones. The space between the bone ends (epiphysis) and the shaft (diaphysis) is increased. Bone density is reduced.
Blood tests
- The blood levels of calcium, phosphorus, alkaline phosphatase, vitamin D, and parathyroid hormone are checked.
- In nutritional rickets, calcium may be low or normal.
- The phosphorus level is often low.
- The alkaline phosphatase level is raised.
Treatment of Rickets
Treatment depends on the cause and must be guided by your child's doctor. Do not give high-dose vitamin D without medical advice, because too much can raise blood calcium to dangerous levels.
- For nutritional rickets, doctors prescribe a course of higher-dose vitamin D, usually for several weeks to a few months, followed by a lower daily maintenance dose. Calcium supplements are often added.
- Make sure your child gets enough calcium from milk, fortified milk, or other calcium-rich foods.
- Safe, short sun exposure helps the skin make vitamin D, but avoid sunburn; babies under 6 months should be kept out of direct sun.
- Bracing or surgery may be needed for severe bone deformities. If treated while the child is still growing, deformities often improve.
HP Thoughts: Kids are adorable but could be big headaches if afflicted by illnesses or diseases. Not only are they difficult to administer medicine but also a handful to take care of. One ailment that disturbs them is the sore throat. Do you know how to deal with it? Read our article: Natural Sore Throat Remedies For Kids.
Sources
- Rickets, MedlinePlus
- An Overview of Rickets in Children, Kidney International Reports (PMC)
