The board certified allergists and clinical immunologists at Riley Hospital for Children at Indiana University Health evaluate and treat children who get recurrent infections because of defects in their immune system. Our physicians evaluate children who have an immune system that is “overactive,” which may show up as the classic allergy, and “underactive,” which means their immune system is deficient. A defective immune system leaves the child unprotected and may lead to recurrent infections.
If your child suffers from recurrent infections, an immune evaluation may be needed. Immune deficiency conditions are rare and are not the only reason for recurrent infections in children. There are four general reasons why children have recurrent infections. Those reasons include:
- Exposure to others
- Physical reasons related to the anatomy or structure of the child
- Problems with the immune system such as:
- An overactive immune system, which results in the classic allergy
- An underactive immune system, which can be defined as immune deficiency
- Other, which includes recurrent infections that are never totally cured
Exposure To Others
Exposure to other people is the most common reason for recurrent infections in children. A noted study from 1964, conducted in Cleveland, Ohio, pinpointed factors that are associated with recurrent infections. Those factors include the age of the patient, the size of the family, the season and school exposure.
Average Respiratory Tract Infections by Age
|Age||Number of illnesses/year||Range (min to max)|
A one-year-old child may average 8 colds per year, but may have playmates who average anywhere from 1 to 17 per year. This number of opportunities for exposure can be frustrating for a concerned parent.
Family size also impacts the number of respiratory illnesses a child may be exposed to. The larger the family, the greater the chance for infection.
|Family size||Illnesses per person per year (respiratory)|
The time of year also affects respiratory tract illness. The Cleveland study showed that peak times of year for respiratory tract illness were between September and March. If your child experiences illness during summer months or there is no change in frequency at other times of year, an immune problem may be the cause.
The Cleveland study also considered school exposure. The study found that once a child was in school, respiratory tract infections increased. If a child had younger siblings, their risk of infection also increased with the school attendance of the older child.
Over the years, there have been many studies looking at the incidence of infection in children who attend daycare. Attending daycare increases the risk of upper respiratory tract infections anywhere from two to eight times. When the child is in a one-on-one situation, just the child and the attending adult, they do better. The most important consideration as to why a child is having recurrent infections is exposure to others.
The second reason why a child may have recurrent infections is physical. The child’s structure or anatomy—how the child is made—may be the reason for recurrent illness.
Some physical reasons for recurrent infections include:
- Circulation issues, such as those caused by sickle cell disease, diabetes, kidney ailments and heart disease.
- Obstruction issues, as caused by Eustachian tube blockage in the ear, cystic fibrosis or stenosis, which is the abnormal narrowing of a passageway in the body.
- Foreign bodies, such as shunts, catheters, valves or aspirated foreign bodies (something unusual that is breathed in by the child).
- Broken barriers when a protective system (like the skin) of the body is compromised, such as eczema, burns or midline sinus tracts.
- Other issues in the body, such as abnormal cilia, which are hair-like structures in the respiratory tract. The respiratory tract is lined with cells that make mucus and the cilia in those cells propel the mucus.
- Irritants that are not part of the physical body. Irritants such as cigarette smoke or strong smells can increase the risk of respiratory tract illness.
Deficient Immune System
The third reason why children may have recurrent infections is a deficient immune system.
This deficiency may occur in two major areas:
- An overactive immune system, which may result in the classic allergy.
- An underactive immune system, which may indicate a deficient immune system.
Allergic conditions may lead to infection. Those illnesses include allergic rhinitis (the immune system overreacts to particles that are breathed in), atopic dermatitis (an itchy skin disorder) and asthma.
Allergic rhinitis may be associated with as many as one-third of cases of serous chronic fluid in the ears. Infectious complications of allergic rhinitis may also include chronic sinusitis (nasal inflammation).
Those with atopic dermatitis who are constantly scratching and breaking down the skin barrier may suffer from recurrent skin infections.
Recurrent pneumonia, a serious lower respiratory tract infection, may actually be asthma.
Deficient Immune System
Immune deficiency can be primary or secondary. The primary immune deficiencies are when the immune systems of the body do not work properly. There are a number of secondary immune deficiencies that are the consequence of other conditions. The immune system needs time to mature (which explains why recurrent infections are common in children). The immune system needs nourishment because good nutrition is essential for good health. The immune system needs help from other body systems. Below are the conditions that have been associated with recurrent infections caused by primary and secondary immune deficiency.
Primary Immune Deficiency
Primary immune deficiencies are rare conditions. The most common is selective immunoglobulin A (IgA) deficiency, which may be seen in one in 500 people. Beyond this, the incidence of immune deficiency is one per 1,000 in some conditions and 1 in 1,000,000 in others.
The immune system is divided into four areas. Each area has its own type of infection. The type of infection, where it is happening and the nature of the organisms that are causing the infections help determine where the defect is.
The four areas of immune dysfunction are:
- T cells
- B cells
- Polymorphonuclear cells
- T cell defects: T cells are the most important immune functioning cells. When these do not work, the most severe forms of immune deficiency will occur. These illnesses strike early in life. Infants have recurrent infections caused by unusual organisms and fail to thrive. There may be a family history of these illnesses.
- B cell defects: The B cell is responsible for antibody protection. Defects of this system are the most common. The hallmark is infection with specific organisms that cause high fever and invasive disease.
- Polymorphonuclear cell defects: These defects are uncommon. Children with defects of these cells may have recurrent skin infections with staphylococcus or recurrent fungal infections.
- Complement defects: The complement system is part of the immune system. These defects are rare.
Knowing what type of organism is responsible for the infection helps define the possible defect in the immune system.
Secondary Immune Deficiency
Secondary immune deficiency may be caused by the following:
- Premature birth
- Hereditary or rare metabolic conditions
- Immunosuppressive agents like drugs, irradiation or oral steroids
- Infectious diseases
- Cancer and blood disorders
- Surgery or trauma
The Diagnosis Of Immune Deficiency Conditions
A patient’s history helps determine what studies need to be done. The history plus results of studies should help in forming the diagnosis. Once a diagnosis is made, treatment can be defined for the specific defect.
Clinical symptoms of immune deficiency vary by age.
Clinical symptoms that may occur from birth to six months include:
- Low calcium
- Heart disease
- Unusual appearance (facial features may be a clue)
- Delayed separation of the umbilical cord
- Very high or very low white blood cell counts
- Thrush that is recurrent and resistant to treatment
- Failure to thrive
- Swollen lymph nodes
- Severe skin conditions
- Bloody stool
- Draining ears
- Mouth ulcers
Clinical symptoms (occurring in addition to the infections) that may occur from six months to five years include:
- Severe infectious mononucleosis
- Paralytic disease after oral polio vaccine
- Recurrent infections with staphylococcus
- Problems with the fingernails and toenails
- Endocrine problems and infections
- Short stature
- Fine hair
- Severe chicken pox
- Swollen, large lymph nodes
- Recurrent pneumonia
- Bone infections
Clinical symptoms (occurring in addition to the infections) that may occur in older children include:
- Certain skin conditions
- Sinopulmonary (sinus and lung) infections
- Neurologic deterioration
- Spider-like blood vessel patterns on the skin
- Recurrent infections with neisserial (a type of bacteria) organisms
- Malabsorption syndromes
- Enlarged spleen
- Autoimmune illnesses
- Candida (yeast) infections
Clinical Immunology Appointments
To get an appointment, you need a referral from your primary care physician. If you are referred to an allergist, but require the additional services of a hematologist, we will direct you to the appropriate provider. We prefer to review all patient records before your first visit. Frequently, blood tests are needed to help with the evaluation. Our clinic uses the labs at Indiana University Health. All appointments for immune evaluations should be performed at the Riley Outpatient Center at IU Health.