Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Pediatric PPT 3 Childhood Infection Immunological Profile Lecture Notes
Childhood Infection-
Immunological Profile
? Musculoskeletal infections in children
Pyomyositis
Septic arthritis
Osteomyelitis
? They are called "deep seated infections"
? Rare
? Not present in immunocompetent children
Immunoglobulin levels vs. age
Innate and adaptive immunity
Classified as
PRIMARY
IMMUNODEFECIENCY
SECONDARY
? TCELL DEFECT
IMMUNODEFECIENCY
? B CELL DEFECT
DRUGS
? COMPLEMENT DEFECT
RADIATION
? PHAGOCYTIC DEFECT
SPLENECTOMY
MALNUTRITION
INFECTIONS
When to suspect immunodeficiency ?
? In every case of musculoskeletal infection
Special y when....
Very frequent infections
Very severe infections
Family history
Unusual clinical presentation
Unusual microorganism
Longer duration of treatment
Not responding to treatment
Additional clues..
? >8 ear infections per year
? >2 serious sinus infections per year
? >2 months treatment with poor result
? Requirement of iv antibiotics
? Failure to thrive with or without diarrhea
At Any Age...
? History for secondary immunodeficiency
Diet
Medication
Infections
Immunization
Splenectomy
Radiation
Systemic illness
Age of presentation
? Onset before age 6 mo suggests a T-cel defect
? Onset between the age of 6 and 12 mo may suggest combined B- and T-cel
defects or a B-cel defect
? Later than 12 mo usual y suggests a B-cel defect or secondary
immunodeficiency
Detailed history
Upto 6 months
? History of newborn seizures, cardiac anomaly
? Delayed cord detachment, recurrent infection
? Diarrhea, pneumonia, oral thrush, FTT
? Bloody stools, draining ears, eczema
6 months to 5 years
? Persistent thrush, nail dystrophy, endocrinopathies
? Short stature, fine hair, severe varicella
? Oculocutaneous albinism with recurrent infection
? Lymphadenopathy, dermatitis, pneumonia, osteomyelitis
Characterstic features
Predominant T cel
Gram positive and
neg bacteria,
Early onset (2-6
mycobacteria,CMV,
mnths)
EBV, and fungi ?
candida
Characterstic features
Predominant B cel
Pneumococci,staph,
Onset after 5-7 months of strepto,enteroviruses,giard
age
ia
Characterstic features
Phagocytic defect
Staph, pseudomonas,
Early onset
candida, nocardia
Characterstic features
Compliment defect
Onset at any age
Pneumococci and neiserria
Muscukoskeletal Infection in HIV patients
? Arthalgia and myalgia-symptom of acute infection
? Staphylococcus aureus, Streptococcus pyogenes, Mycobacterium
tuberculosis, Nocardia and Cryptococcus common organisms
? Myositis common- bacterial infections, opportunistic and direct viral
infection
? Tuberculous osteomyelitis common
? Bacillay angiomatosis
? Knee and ankle arthritis common
Examination
Clinical y-
? BCG scar absent
? wasted, stunted, malnourished
? Skin eczema present, hypopigmented patches
? Oral thrush, nail fungal infection
? Absence of tonsils and lymph nodes
? Respiratory system-b/l ronchi , wheeze, crepts
Screening tests
Skin testing for
CBC with
delayed
manual
hypersensitivity
differential
Quantitative Ig
Antibody titers
measurements
Laboratory tests to assess
immune function
(1) T cell: Enumeration (flow cytometry), functional assays (mitogen
response, DTH skin tests)
(2) B cell: Enumeration, circulating antibody levels
(3) Macrophage: Enumeration, functional assays (nitroblue
tetrazolium)
(4) Complement: Direct measurement of complement components,
complement hemolysis assay
Key Points
? Done in every child with musculoskeletal infection
? High index of suspicion
? Thorough history and complete physical examination is must
? Begin with screening tests and appropriate additional testing as
required
? Early diagnosis and prompt treatment could be life saving
References
? Nelsons textbook of pediatrics 19 th ed
? Diagnostic Approach to Primary Immunodeficiency Disorders; indian
pediatrics,june 2013
? Approach to the Patient With Suspected Immunodeficiency:
Immunodeficiency Disorders: Merck Manual
This post was last modified on 07 April 2022