Download MBBS Pediatric PPT 3 Childhood Infection Immunological Profile Lecture Notes

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