Recurrent infections in a child

(Suspected Immunodeficiency)

Children presenting with recurrent, severe, or unusual infections present a diagnostic challenge.

Children with normal immune systems can experience 4 to 8 minor childhood infections per year (usually URTI). They are often exposed to infections from siblings or nursery; or second hand smoking. However, their growth and development is not affected and they recover promptly.

Those with atopy get recurrent or persisting URTI.

Red Flags:

Suspect immunodeficiency if recurrent infections are CRAMPS:

– Complicated / deep seated infections

– Resistant to treatment

– Atypical organisms

– Multiple locations

– Persistent infections

– Severe infections

 

Onset <6months (? T-cell disorder)

Onset 6 – 12m (either combined or B-cell)

Onset >12m age (secondary causes or B-cell)

Refer for assessment if:

 

– 2 or more serious bacterial infections

– Associated failure to thrive

– Vaccine preventable infection

– Opportunistic infection

  (Pneumocystis carinii)

– Chronic non-responding infection

– F/h/o immune disorder

Causes of Primary Immunodeficiency:

B-cell (Humoral) disorder:

 – Selective IgA deficiency

– X linked Agammaglobulinemia

T-cell (Cellular) disorders:

 – X linked lymphoproliferative disorder

 – Chronic mucocutaneous candidiasis

Combined B & T cell:

– Severe Combined Immunodeficiency (SCID)

– Ataxia Telangiectasia

– Wiskott Aldrich synd, DiGeorge synd

Phagocytic cell disorder:

 – Chronic Granulomatous disease

 – Cyclical neutropenia 

Complement deficiencies

Causes of Secondary Immunodeficiency:

 – HIV / AIDS

 – Diabetes Mellitus

 – Malnutrition / Chronic illness

 – Post viral infection

 – Malignancy

 – Nephrotic syndrome

 – Downs syndrome 

 – Immunosuppressive treatment

 – Severe burns

History:

– Which infections have caused concern?

– Recurrent viral / fungal / mycobacterial (? T-cell)

– Recurrent sepsis (?complement defi)

– Recurrent skin inf (? neutrophil disorder)

– Site, duration, response to treatment?

– Is there fever during these illnesses?

– How frequent antibiotics  needed 

– Do antibiotics help?

– Any organisms isolated by lab?

– Any hospitalisations / operations needed?

 

Also ask:

Delayed umbilical cord separation (>3weeks)

Is infant thriving?

Is development affected?

Immunisation history?

Any severe reaction to live vaccine

 (? BCG suppuration)

Any underlying illness (?Diabetes)

High risk for HIV?

Unexplained fractures?

Autoimmune vasculitis/ hepatitis?

F/h/o immune problems? or early childhood deaths (?SCID)

 

Examination:

– Growth (plot Ht, Wt, HC)

– Developmental assessment, Ataxia?

– Any dysmorphism, white forelock hair?

– Lymphadenopathy- localised / generalised?

– Tiny LN, Tonsils despite recurrent sore throat?

– Ear, Nose, Throat exam

– Oral ulcers?

– Skin- eczema/ granuloma/ vesicles/ pyoderma?

– Chest crackles? Finger clubbing?

– Hepatospleenomegaly?

Investigations:

 

Consider Initial screening:

– FBC, film, ESR

– U&E, LFT, Ca, IgG,IgM,IgA,IgE

– Antibody response to Tetanus, HiB & Pneumococcus (age dependent)

– Appropriate swabs / cultures

– Test for HIV if at risk?

 

Further Specialist tests:

– Lymphocyte subset assay

– Lymphocyte proliferation

– Neutrophil oxidation burst

– Complement assay C3, C4, CH50

 

Management:

– Consider higher dose of antibiotics and longer duration

– Are prophylactic antibiotics needed?

– Is extra dose of vaccine needed?

– Avoid live attenuated vaccines (MMR, BCG, Varicella)

 

Link with Immunology/ Infectious Disease specialist for 

   – Complicated infections

   – Regular immunoglobulin therapy

   –  Interferon / Enzymes

   – Bone Marrow Transplant