Primary immunodeficiency, suspected immunodeficiency, approach to immunodeficiency, prenatal diagnosis of immunodeficiency

1. Approach to a child with
suspected immunodeficiency &
prenatal diagnosis of primary
immunodeficiency (PID)
Dr. Dilip Choudhary
Department of Pediatrics,
Mata Chanan Devi Hospital, New Delhi

2. Physiology
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3. Innate and adaptive immunity
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4. Case
5 months old male child, 1st by birth order, born of
non-consanguineous marriage, admitted with
complains of
c/o fever for 5 days, moderate grade, intermittent
c/o breathlessness for 4 days
c/o cough, cold for 4 days
c/o watery loose stools for 4-5 days
No h/o bottle feeding
No suck rest suck cycle, sweating over forehead
No h/o recurrent regurgitations20/12/2017 Dr. Dilip Choudhary 4

5. Past h/o similar complain one month
back required hospitalization for 8 days,
received iv antibiotic for pneumonia.
Family history not significant
Immunized for age
Development- appropriate for age
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6. Examination:
Pulse- 120/ min, RR- 50/min, noisy breathing
Anthropometric parameter- WNL
General physical examination- normal except oral
thrush
• Respiratory system- nasal flaring, chest indrawing
+nt, BSBE, B/L crepts +nt
• CVS- both heart sounds normal, no murmer
• CNS- irritable, T/P/R normal
• P/A- soft, Non-tender. Liver 2 cm palpable, soft,
rounded margin, smooth surface, liver span 6.5cm,
spleen- NP
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7. Differential diagnosis
• Congenital malformations of the upper or the
lower respiratory tract
• Cardiac problem (CHD especially LtRt shunt)
• Recurrent aspirations (GER)
• Foreign body aspiration
• Defects in the clearance of airway secretions
especially cystic fibrosis, ciliary abnormalities.
• Immunodeficiency disorders
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8. Investigation:
• TLC- initially high, normalise with 4-5 days
of antibiotic course
• CXR- pneumonitis
• Stool R/M, urine R/M- normal
• Blood culture- no growth
• 2D ECHO- PFO
• USG abdomen- normal study
• CT chest- pneumonia, no congenital
anatomical defect
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9. Course during hospital stay:
All investigations improved but baby had
intermittent fever spikes in spite of
antibiotic up gradation.
Immunoglobulin level- below normal range
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10. Immunodeficiency Disorder
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11. When to suspect immunodeficiency
Unusual, chronic, or recurrent infections such as:
• ≥1 systemic bacterial infection (sepsis, meningitis)
• ≥2 serious respiratory or documented bacterial
infections (cellulitis, abscesses, draining otitis
media, pneumonia) within 1 yr.
• Serious infection occurring at unusual sites (liver,
brain abscess)
• Infection unusual pathogen
• Infection with common childhood pathogen but of
unusual severity
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12.  Family history of early infant death or a known
immunodeficiency disorder
Additional clues:
• FTT with or without chronic diarrhea
• Persistent infection after receiving live vaccines
• Chronic oral or cutaneous moniliasis
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13. Why diagnosis is difficult
I˚ immunodeficiency
diseases are not screened
for at any time during life
Most affected do not
have abnormal physical
features
Extensive use of
antibiotics may mask the
classic presentation.
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14. Classification of Immunodeficiencies
Primary immunodeficiency (Hereditary) Secondary immunodeficiency (Acquired)
 Predominant antibody defect
 Combined T and B cell defect
 Other cellular immunodeficiency
 Complement defect
 Phagocytic defect
 Diseases of immune
dysregulation
 Systemic disorder:
Diabetes,
HIV infection,
Undernutrition,
 Immunosuppressive T/t :
cytotoxic chemotherapy,
Bone marrow transplant,
Radiation therapy,
Corticosteroids etc)
 Prolonged serious illness
(critically ill, hospitalized
patients)
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15. Predominant antibody deficiencies
(Humoral immunodeficiency)
Most common PIDs
• XL agammaglobulinemia (Bruton agammaglobulinemia)
• AR agammaglobulinemia
• Common Variable Immunodeficiency (CVID)
• Selective IgA deficiency
• Hyper-IgM syndromes
• Ig heavy-chain gene deletions- AR
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16. Combined T and B cell disorders
• Severe combined immunodeficiency (SCID)
• Omenn syndrome
• Combined immunodeficiency
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17. Other cellular immunodeficiency
• Wiskott-Aldrich syndrome (WAS)
• Ataxia-telengectiasia (AT)
• DiGeorge anomaly
• Hyper IgE syndrome (HIGE)
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18. Complement disorders
• C1q, C1r, C2-C9 deficiency
• C1 inhibitor
• Factor I deficiency
• Factor H deficiency
• Factor D deficiency
• Properdin deficiency
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19. Phagocyte disorders
• Chronic granulomatous disease (CGD)
• Leukocyte adhesion defect
• Chediac Higashi syndrome
• Myeloperoxidase deficiency
• Cyclic neutropenia (elastase defect)
• Neutrophil G6PD deficiency
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20. Diseases of immune dysregulation
• Familial Hemophagocytic Lymphohistiocytosis
(FHLH)
• Autoimmune Lymphoproliferative syndrome
(ALPS)
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21. Characteristic features of PID
Predominant T cell defect
Age at onset Specific pathogen Affected
organ
Special feature
Early age, 2-
6 months
Bacteria: Gram +ve
and Gram –ve,
mycobacteria.
Virus: CMV, EBV,
Varicella, adenovirus.
Fungus: candida,
pneumocystis jiroveci
-Extensive
mucocute-
neous
candidiasis
-Lungs
-GI
- Failure to
thrive
- Protracted
diarrhea
- Postvaccination
disseminated
BCG or varicella
- Hypocalcemic
tetany in
infancy
- Graft vs host
disease20/12/2017 Dr. Dilip Choudhary 21

22. Predominant B cell defect
Age at onset Specific
pathogen
Affected organ Special features
After maternal
Ab diminish,
usually after 5-
7 months of
age
Bacteria:
pneumococci,
streptococci,
staphylococci,
mycoplasma
Virus:
enterovirus
Parasite:
Giardia,
Cryptosporidia
- Recurrent
sinopulmonary
infection
- Chronic GI
symptoms,
malabsorption
- Arthritis
- Enteroviral
meningoencep
halitis
-Autoimmunity
-Post vaccination
paralytic polio
-Lymphoreticular
malignancy:
lymphoma,
thymoma
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23. Phagocyte (Granulocyte) defect
Age at onset Specific
pathogen
Affected organ Specific
features
Early onset Bacteria: staph,
pseudomonas,
Klebsiella,
salmonella
Fungi: candida,
nocardia,
aspergillus
Skin: abscess,
impetigo,
cellulitis
Lymphnode:
suppurative
adenitis.
Oral cavity:
gingivitis,
mouth ulcer.
Prolonged
attachment of
umbilical cord.
Poor wound
healing.
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24. Complement defect
Age at
onset
Specific
pathogen
Affected organ Special feature
Any age Bacteria:
Pneumococci,
Neisseria
Infection:
meningitis,
arthritis,
septicemia,
recurrent
sinopulmonar
y infections
Autoimmune
disorder: SLE,
Vasculitis,
scleroderma,
dermatomyositis,
glomerulonephriti
s
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25. Approach to child with immunodeficiency
History (symptoms, age at onset)
Physical examination
Investigation
Treatment
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26. The European Society of
Immunodeficiencies (ESID)
10 warning signs for suspicion of PID:
• 4 or more new ear infections within 1 year.
• 2 or more serious sinus infections within 1 year.
• 2 or more pneumonias within 1 year.
• 2 or more deep-seated infections including
septicemia.
• 2 or more months on antibiotics with little
effect.
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27. • Failure to gain weight or grow normally.
• Recurrent, deep skin or organ abscesses.
• Persistent thrush in mouth or fungal infection on
skin.
• need for intravenous antibiotics to clear infection
• A family history of PID.
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28. Common clinical features
• Recurrent respiratory tract infections
• Severe bacterial infection
• Persistent infection with incomplete response
• Persistent sinusitis/mastoiditis
• FTT/Growth retardation
• Diarrhea/malabsorption
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29. Occasionally present:
• Lymphadenopathy
• Hepatosplenomegaly
• Recurrent meningitis
• Pyoderma
• Deep infections: osteomyelitis, cellulitis
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30. Age at presentation
Newborn and young infant
(0-6 months)
In Infant and young
children (6mths - 5 yrs)
In older children (>5 years)
and adults
• SCID
• LAD
• DiGeorge anomaly
• Wiskott-Aldrich
syndrome
• X- linked hyper IgM
syndrome
• CGD
• Hper IgE syndrome
• Chediak- Higashi
syndrome
• Chronic
mucocuteneous
candidiasis
• X- linked
lymphoproliferative
syndrome
• X linked
agammaglobulinemia
• Ataxia telangiectasia
• Common variable
immunodeficiency
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31. Physical examination
Mouth: Skin
Oral ulcers Vitiligo, Albinism
Oral candidiasis Alopecia, Eczema
Periodontitis, gingivitis Erythroderma
Recurrent abscess
Extremities Endocrinologic
Clubbing of nails Hypoparathyroidism
Arthritis Growth hormone deficiency
Nail candidiasis
Hematologic
Hemolytic anemia
Thrombocytopenia
Neutropenia20/12/2017 Dr. Dilip Choudhary 31

32. Physical examination
Clinical feature Disorder
Skin
Vitiligo
Alopecia
B-cell defect
Oculocuteneous albinism
Sparse and /or hypopigmented
hair
Chediak-Higashi syndrome, Griscelli syndrome
Eczema Wiskott-Aldrich syndrome, hyper IgE syndrome, IgA
deficiency
Severe dermatitis, Erythroderma Omenn syndrome
Recurrent abscess with
pulmonary pneumatocele
Hyprt IgE syndrome
Recurrent abscess or cellulitis Hyper IgE syndrome, Chronic granulomatous disease ,
Leucocyte adhesion defect
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33. Mouth
Oral ulcers CGD, SCID, congenital neutropenia
Oral or nail candidiasis T-cell defect, SCID,
Periodontitis, gingivitis, stomatitis Neutrophil defect
Extremities
Clubbing of the nails Chronic lung disease due to antibody defect
Arthritis Antibody defect, WAS, hyper Ig M syndrome
Endocrinologic
Hypoparathyroidism DiGeoge syndrome, mucocuteneous
candidiasis
Growth hormone deficiency X-linked agammaglobulinemia
Hematological
Hemolytic anemia B- and T-cell defect, ALPS
Thrombocytopenia, small platelet WAS
Neutropenia Hyper IgM syndrome, WAS, CGD
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34. Screening immunologic testing in child
with recurrent infection
CBC with DLC & ESR (Hemogram)
Absolute neutrophil count Normal results rules out:
- Congenital or acquired neutropenia
- Leucocyte adhesion defect
(persistently elevated ANC, LAD is
suspected even in absence of signs of
infection)
Absolute lymphocyte count Normal results rules out: T cell defect
Platelet count Normal results rules out: WAS
ESR Normal results : chronic bacterial or
fungal infection unlikely
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35. Screening test for T- cell defect
• Absolute lymphocyte count Normal results rules out T cell defect
• Flow cytometry To check for naïve T cells (CD3+CD45RA)
Screening test for B cell defect
• IgA If abnormal, measure IgM, IgG
• Antibody titre to protein & polysaccharides antigens (Isohemagglutinins and Ab to blood
group substances, vaccine antigens)
Screening test for phagocytic cell disorder
• Absolute neutrophil count
• Respiratory burst assay
Screening test for complement deficiency
• CH50 Measures intactness of the entire complement
pathway. Low value indicates complement
deficiency.
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36. Evaluation of B cell defect
(A) Measure IgA level
Normal low
Selective IgA deficiency measure IgM &IgG
is excluded (MC B-cell defi) if low, check whether Ig level
is low because of low production
or protein loss
 Patient receiving steroid or who has protein loss (protein losing
enteropathy, nephrotic syndrome) has low IgG but production
normal.
 Antibody titres are not interpretable after blood transfusion/ FFP/
IVIG.
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37. (B) Isohemagglutinin titre ( Ab to type A and B red cell antigen):
 Measures IgM antibodies
 Isohemagglutinin may be absent till 2 yrs of age and always absent if
blood group is AB.
(C) Antibody response to protein & polysaccharide antigen: (detect IgG)
measure titre of Ab to anti pneumococcal Ab before and
DPT/ Hib after 3 wks of immunization with PPSV
if titre low, measure Ab to if titre is low, boost with PCV twice
Diphtheria, tetanus toxoid (1 month apart) then give PPSV
Before and 2 months after 1 month later
DPT/ DT booster measure Ab 3 wks later, if IgG &IgM
is low, indicates significant/ permanent
B cell defect.
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38.  if results of above tests is normal but Ig Level is low  evaluate for
possible urinary or GI loss of Ig (nephrotic syndrome, protein
losing enteropathies, intestinal lymphangietasia) .
 Very high concentration of 1 or more Ig suggest- HIV, CGD, chronic
inflammation or autoimmune lymphoproliferative syndrome.
(D) If agammaglobulinemia is suspected:
B-cell enumeration with flowcytometry (to distinguish CVID &XLA)
B-cells absent B-cells present
X-linked agammaglobulinemia CVID/ IgA defi/ Hyper IgM synd
↑ed susceptibility to persistent more problem with auto-
entroviral infection immune D’se &lymphoid
hyperplasia
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39. Evaluation T-cell defect
 (A) Any infant with lymphopenia
T-cell enumeration by flow cytometry
(normally CD3+ T cells constitute 70% of peripheral lymphocytes)
 (B) Infant with SCID (lymphopenic at birth)
flowcytometry for Ab to naïve (CD45RA) & memory T-cell (CD45RO)
normal infant infant with SCID
>95% of T-cells are naïve T-cells most of the T-cells are
memory T-cells(CD45RO)
because these are transplacentally
transferred maternal T cells
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40. Evaluation for phagocytic cells defect
 Recurrent staphylococcal abscess or gram –ve infection
screen by measuring neutrophil respiratory burst after
phorbol ester stimulation (flow cytometric assessment)
 Leucocyte adhesion defect :
• diagnosed by flow cytometric assays of lymphocytes or
neutrophils, using Ab to CD18 or CD11 (LAD1) or to CD15 (LAD2).
• Leukocytosis that persists between infections
 Chronic granulomatous disease: molecular testing for specific
mutation ( mutation in genes encoding 5 different proteins ),
important for genetic counselling (1 type is X linked and other 4
are autosomal recessive).
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41. Treatment
• Primary antibody production (B-cell) defect:
Antibiotic for documented infection
Regular IVIG (approx 400mg/kg per month)
• Primary T-cell defect: cultured unrelated thymic
tissue transplant (for DiGeorge syndrome) or stem
cell transplant
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42. Prenatal diagnosis of PID
• >220 disorder have been described
• Molecular defects detected in approximately 80%
• Important to provide appropriate genetic counselling
• Most are recessive traits (several are AR and others XR)
• X-linked immunodeficiency disorder:
- Hyper IgM syndrome
- X-linked lymphoproliferative syndrome
- X-linked agammaglobulinemia
- X-linked SCID
- WAS
- Properdin deficiency (complement defect)
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43. Intrauterine diagnosis:
• By enzymatic analysis of adenosine deaminase and purine
nucleoside phosphorylase deficiency on amnion cells before 20 wks
of gestation.
• Diagnosis of autosomal or X-linked defect
mutation is known in family mutation not known
mutational analysis on sample appropriate test of phenotype
obtained by CVS or amniocentasis or function on sample obtained
by fetoscopy at 18-22 wks.
• Same procedure can be done on cord samples but its not routine
included in neonatal screening
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44. Questions
Q1. A 3 yr old girl has a h/o recurrent, serious skin and
soft tissue infections caused by Staph aureus and group
A Streptococcus. The initial screening laboratory
evaluation for possible immunodeficiency includes all of
the following EXCEPT:
(a)Complete blood cell count and manual differential
(b)Absolute lymphocyte count
(c)Platelet count
(d)CH50
(e) Immunoglobulin levels
Ans: (d)
This child with recurrent Staphylococcus aureus and GAS
skin abscesses most likely has a B-cell defect.
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45. Q2. Which of the following is an effective screening
test for T-cell function?
(a) Absolute lymphocyte count
(b) Flow cytometry for CD4 (helper) and CD8
(cytotoxic) T cells
(c) Respiratory burst assay
(d) Candida skin test
(e)Mumps antibody titer after mumps vaccination
Ans: (d)
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46. The Candida skin test:
• Most cost-effective test of T-cell function.
• Adults and children >6 yr of should be tested by
intradermal injection with 0.1 mL of a 1:1,000
dilution of Candida albicans extract.
• If the test result is -ve at 24 hr, 48 hr, and 72 hr, a
1:100 dilution should be used, which also can be
used for the initial testing of children < 6 yr of
age.
• If the Candida skin test result is positive
(erythema and induration of ≥ 10 mm) at 48 hr
and that is greater than at 24 hr, all primary T-cell
defects are precluded,
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47. Q3. Useful tests for evaluation of possible B-cell
(antibody) deficiency include all of the following
EXCEPT:
(a)Isohemagglutinins
(b)Antibodies to tetanus
(c) Flow cytometry for CD3 cells
(d) Serum IgA level
(e) Total IgG level
Ans: (c)
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48. Q4. Complications of intravenous immunoglobulin
(IVIG) therapy include all of the following EXCEPT:
(a) Anaphylaxis
(b) Fluid overload
(c) Transmission of HIV
(d) Aseptic meningitis
(e) Systemic reactions
Ans: (c)
The ethanol used in preparation of IVIG inactivates
HIV; and an organic solvent/detergent step
inactivates hepatitis B and C viruses. There has been
no documented transmission of HIV by any of these
preparations.
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49. Q6. The recommended treatment for severe
combined immunodeficiency (SCID) is:
(a) Gene therapy
(b) Monthly IVIG
(c) Monthly IVIG and IFN-γ
(d) Monthly IVIG and IL-8 monoclonal antibody
(e) Stem cell transplantation
Ans: (e)
SCID is a true pediatric emergency
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50. Take home message
• Require high index of suspicion
• Do screening tests and appropriate additional
testing as required
• Early diagnosis and prompt treatment could
be life saving
• Teach patients how to avoid infections ,and do
required preventive measures
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51. Bibliography
• Nelsons textbook of pediatrics 20th ed
• Diagnostic Approach to Primary
Immunodeficiency Disorders; Indian
pediatrics, June 2013
• Approach to the Patient With Suspected
Immunodeficiency: Immunodeficiency
Disorders: Merck Manual
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