IMMUNE SYSTEM. IMMUNE SYSTEM. PECULIARITIES of ITS PECULIARITIES of ITS

FUNCTIONING. FUNCTIONING. INSPECTION METHODS IN INSPECTION METHODS IN

CHILDREN. SEMIOTICS. CHILDREN. SEMIOTICS. ССARE FOR PATIENTSARE FOR PATIENTS

The immune system includes the The immune system includes the primary primary lymphoid organs (thymus, bone marrow, lymphoid organs (thymus, bone marrow, and probably liver) and the and probably liver) and the secondarysecondary lymphoid organs (lymph nodes, spleen, lymphoid organs (lymph nodes, spleen, and gut-associated lymphoid tissue and gut-associated lymphoid tissue [GALT]). [GALT]).

The functions of the immune The functions of the immune systemsystem

are basically two types: are basically two types: nonspecificnonspecific and and specific.specific. Nonspecific immune defenses Nonspecific immune defenses are activated on exposure to any foreign are activated on exposure to any foreign substance but react similarly regardless of substance but react similarly regardless of the type of antigen; they are unable to the type of antigen; they are unable to identify the antigen. The principal identify the antigen. The principal component of this system is phagocytosis, component of this system is phagocytosis, the process of ingesting and digesting the process of ingesting and digesting foreign substances. Phagocyte cells are foreign substances. Phagocyte cells are composed of neutrophils and monocytescomposed of neutrophils and monocytes

SpecificSpecific defenses are those that have the defenses are those that have the ability to recognize the antigen and ability to recognize the antigen and respond selectively. The components of respond selectively. The components of adaptive immunity are humeral immunity adaptive immunity are humeral immunity and cell-mediated immunity. The cells and cell-mediated immunity. The cells responsible for these two forms of responsible for these two forms of immunity are the lymphocytes, specifically immunity are the lymphocytes, specifically B-lymphocytes and T-lymphocytes.B-lymphocytes and T-lymphocytes.

Humoral immunityHumoral immunity Humeral immunity is involved with antibody Humeral immunity is involved with antibody

production and complement. The principal cell production and complement. The principal cell involved in antibody production is the B-involved in antibody production is the B-lymphocyte.lymphocyte. Five classes of antibodies or Five classes of antibodies or immunoglobulins (lg) have been identified: G, M, immunoglobulins (lg) have been identified: G, M, A, D, and E, each serving a specific function .A, D, and E, each serving a specific function .

On initial exposure to an antigen, the B-On initial exposure to an antigen, the B-lymphocyte system begins to produce antibody, lymphocyte system begins to produce antibody, predominantly lgM, which appears in 2 to 3 predominantly lgM, which appears in 2 to 3 days. This process is referred to as the primary days. This process is referred to as the primary antibody response.antibody response.

Cell-mediated immunityCell-mediated immunity Cell-mediated immunity is involved in a variety of Cell-mediated immunity is involved in a variety of

specific functions mediated by the T-lymphocyte. specific functions mediated by the T-lymphocyte. The T-lymphocyte is so named because it The T-lymphocyte is so named because it passes through the thymus during the passes through the thymus during the differentiation process, which leads to the differentiation process, which leads to the mature T-cell. T-lymphocytes do not carry typical mature T-cell. T-lymphocytes do not carry typical immunoglobulins on their surfaces as do the B-immunoglobulins on their surfaces as do the B-cells. However, they are functionally cells. However, they are functionally heterogeneous in that several subsets have heterogeneous in that several subsets have been identified, including cytotoxic T-cells, been identified, including cytotoxic T-cells, memory T-cells, helper T-lymphocytes, and memory T-cells, helper T-lymphocytes, and regulator T-lymphocytes.regulator T-lymphocytes.

Cell-mediated immunityCell-mediated immunitySpecific functions of T-lymphocytes include: Specific functions of T-lymphocytes include: protection against most viral, fungal, and protection against most viral, fungal, and

protozoan infections and slow-growing bacterial protozoan infections and slow-growing bacterial infections, such as tuberculosis, infections, such as tuberculosis,

rejection of histoincompatible grafts, mediation rejection of histoincompatible grafts, mediation of cutaneous delayed hypersensitivity reactions, of cutaneous delayed hypersensitivity reactions, such as in tuberculin testing, such as in tuberculin testing,

and probably immune surveillance for malignant and probably immune surveillance for malignant cells. cells.

In addition, they also have regulatory functions In addition, they also have regulatory functions within the immune system. within the immune system.

Cell-mediated immunityCell-mediated immunity The immunologic system undergoes numerous changes The immunologic system undergoes numerous changes

during the first year. The during the first year. The newbornnewborn receives significant receives significant amounts of maternal amounts of maternal lgGlgG, which confers immunity for , which confers immunity for about 3 months against antigens to which the mother about 3 months against antigens to which the mother was exposed. During this time the infant begins to was exposed. During this time the infant begins to synthesize his own synthesize his own lgGlgG, and about 40% of adult levels , and about 40% of adult levels are reached by 1 year of age. are reached by 1 year of age.

Significant amounts of Significant amounts of lgMlgM are produced at birth, and are produced at birth, and adult levels are reached by 9 months of age. adult levels are reached by 9 months of age.

The production of The production of IgA, IgD,IgA, IgD, and and IgEIgE is much more is much more gradual, and maximum levels are not attained until early gradual, and maximum levels are not attained until early childhood.childhood.

Cell-mediated immunityCell-mediated immunity Immunoglobulin G (lgG),Immunoglobulin G (lgG), which neutralizes microbial which neutralizes microbial

toxins, reaches adult levels by the end of the second toxins, reaches adult levels by the end of the second year of life. Passive immunity from maternal transfer year of life. Passive immunity from maternal transfer disappears by the beginning of toddlerhood, disappears by the beginning of toddlerhood, necessitating the use of artificial immunizations. necessitating the use of artificial immunizations. Immunoglobulin M (lgM),Immunoglobulin M (lgM), which responds to artificial which responds to artificial immunizing techniques and combats serious infection, immunizing techniques and combats serious infection, attains adult levels during late infancy.attains adult levels during late infancy.

Immunoglobulins A, D, and EImmunoglobulins A, D, and E increase gradually, not increase gradually, not reaching eventual adult levels until later childhood. Many reaching eventual adult levels until later childhood. Many young children demonstrate a sudden increase in colds young children demonstrate a sudden increase in colds and minor infections when entering nursery school or and minor infections when entering nursery school or kindergarten because of the exposure to new antigens.kindergarten because of the exposure to new antigens.

The terms in immunologyThe terms in immunology immunity immunity An inherited or acquired status An inherited or acquired status

in which an individual is resistant to the in which an individual is resistant to the occurrence or the effects of a specific occurrence or the effects of a specific disease, particularly an infectious agent.disease, particularly an infectious agent.

natural immunitynatural immunity Innate immunity or Innate immunity or resistance to infection or toxicity.resistance to infection or toxicity.

acquired immunityacquired immunity Immunity from Immunity from exposure to the invading agent, either exposure to the invading agent, either bacteria, virus, or toxins.bacteria, virus, or toxins.

The terms in immunologyThe terms in immunology active immunity:active immunity: individual actively forms individual actively forms

immune bodies against specific antigens, either immune bodies against specific antigens, either naturally by his having had the disease clinically naturally by his having had the disease clinically or subclinically or articifically by the introduction or subclinically or articifically by the introduction of an antigen (vaccine) into the individual.of an antigen (vaccine) into the individual.

passive immunity:passive immunity: temporary immunity by temporary immunity by transfusing plasma proteins either artificially from transfusing plasma proteins either artificially from another human or an animal that has been another human or an animal that has been actively immunized against an antigen or naturally actively immunized against an antigen or naturally from the mother to the fetus via the placenta.from the mother to the fetus via the placenta.

antibody:antibody: a protein found mostly in serum that is a protein found mostly in serum that is formed in response to exposure to a specific formed in response to exposure to a specific antigen.antigen.

The terms in immunologyThe terms in immunology antigen:antigen: a variety of foreign substances, a variety of foreign substances,

including bacteria, viruses, toxins, and including bacteria, viruses, toxins, and foreign proteins that stimulate the foreign proteins that stimulate the formation of antibodies.formation of antibodies.

antitoxin:antitoxin: antibody formed in response to antibody formed in response to a toxin (antigen).a toxin (antigen).

toxin:toxin: a poisonous substance usually a poisonous substance usually produced by the invading microorganism.produced by the invading microorganism.

toxoid:toxoid: a toxin that has been treated to a toxin that has been treated to destroy its toxic properties but retain its destroy its toxic properties but retain its antigenic quality.antigenic quality.

The terms in immunologyThe terms in immunology vaccine:vaccine: collectively a term to denote any collectively a term to denote any

type of active immunization, such as toxoids or type of active immunization, such as toxoids or attenuated live viruses; specifically a attenuated live viruses; specifically a suspension of disease-causing bacteria or suspension of disease-causing bacteria or viruses that acts like an antigen, stimulates viruses that acts like an antigen, stimulates antibody production, and produces active antibody production, and produces active acquired immunity.acquired immunity.

attenuate:attenuate: reduction of the virulence reduction of the virulence (infectiousness) of a pathogenic microorganism (infectiousness) of a pathogenic microorganism by such measures as treating it with heat, by such measures as treating it with heat, chemicals, or cultivating it on a certain media.chemicals, or cultivating it on a certain media.

Specific (adaptive) defensesSpecific (adaptive) defenses are those that have the ability to are those that have the ability to

recognize the antigen and respond recognize the antigen and respond selectively. The components of adaptive selectively. The components of adaptive immunity are humoral immunity and cell-immunity are humoral immunity and cell-mediated immunity. The cells responsible mediated immunity. The cells responsible for these two forms of immunity are the for these two forms of immunity are the lymphocytes, specifically B-lymphocytes lymphocytes, specifically B-lymphocytes and T-lymphocytesand T-lymphocytes

Normal development of the immune system

After birth, the infant is rapidly colonised by organisms and challenged by waves of transient pathogens. Cellular immunity is active from birth, and although the neutrophil count is relatively low, infants are able to respond to bacterial infection with a leucocytosis. Humoral immunity is less well developed but the maturing system is initially supported by transplacental maternal-derived IgG antibodies and potentially by breast milk factors including IgA. Ig M does not

cross the placenta but infants can produce it in response to infection. In an intact immune system the waning of maternally derived IgG is matched by gradual enhancement of endogenous production but there is a nadir of circulating IgG levels at age 2-3 months. The emergence of specific endogenous antibodies reflects the process, of natural immunisation, and this is accelerated during the preschool years as children average 6-12 short-lived infections each year.

Abnormal development of the immune system

Immunodeficiency is suggested by a history of unusually frequent or severe infections, or by unusual patterns of infection especially if caused by organisms of low pathogenicity. A positive family history is also a powerful guide. Failure to thrive rather than overt infection may be the main manifestation. Modern immunology laboratories are equipped with the tools to test the integrity of each of the main pathways of the immune system, and the classification of disorders has become increasingly functional. Successful management depends upon swift recognition and classification of the disorder, initiation of specific treatments where indicated and meticulous attention to bacteriological and virological investigation of all infectious episodes. Where indicated, life-long immunoglobulin replacement can be very effective.

Clinical manifestationsClinical manifestations

Obviously the most common manifestation is susceptibility to infection early in life, most often by 3 months of age when maternal immunity is low. Specifically the disorder in children is characterized by chronic infection, failure to completely recover from an infection, frequent reinfection, and infection with unusual agents. In addition, the history reveals no logical source of infection. Failure to thrive is a consequence of the persistent illnesses.

If the child should receive a foreign tissue, such as blood supplements, signs of graft-versus-host assey reaction, such as fever, skin rash, alopecia, hepatosplenomegaly, and diarrhea, are expected. Since the reaction requires 7 to 20 days for tissue damage to become evident, the symptoms may be mistaken for an infection. However, the presence of a graft-vs-host reaction increases the child's susceptibility to overwhelming infection and, therefore, is a grave complication.

Diagnostic evaluationDiagnostic evaluation

Diagnosis is usually based on a history of recurrent, severe infections from early infancy, a familial history of the disorder, and specific laboratory findings, which include lymphopenia, lack of lymphocyte response to antigens, and absence of plasma cells in the bone marrow. Documentation of immunoglobulin deficiency is difficult during infancy because of the normally delayed response of the infant to produce his own immunoglobulins and maternal transfer of immunoglobulin G.

Initial Immunologic Testing of the Child with Recurrent Infections Complete Blood Count, Manual Differential, and Erythrocyte

Sedimentation Rate Absolute lymphocyte count (normal result makes T-cell defect unlikely) Absolute neutrophil count (normal result precludes congenital or

acquired neutropenia and (usually) both forms of leukocyte adhesion deficiency, in which elevated counts are present even between infections)

Platelet count (normal result excludes Wiskott-Aldrich syndrome) Howell-Jolly bodies (presence suggests asplenia) Erythrocyte sedimentation rate (normal result indicates chronic bacterial

or fungal infection unlikely)Screening Tests for B-Cell Defects IgA measurement; if abnormal, IgG and IgM measurement Isohemagglutinins Antibody titers to tetanus, diphtheria, H. influenzae, and S. pneumoniae

Initial Immunologic Testing of the Child with Recurrent InfectionsScreening Tests for T-Cell Defects Absolute lymphocyte count (normal result indicates T-

cell defect unlikely) Candida albicans intradermal skin test: 0.1mL of a

1:1,000 dilution for patients older than 6 yr, 0.1mL of a 1:100 dilution for patients younger than 6 yr

Screening Tests for Phagocytic Cell Defects Absolute neutrophil count Respiratory burst assayScreening Test for Complement Deficiency CH50

Diagnostic criteria of primary immunodeficient conditionsClinical:A. Suggestive T-cell deficit:a) systemic illness following vaccination with any alive virus or BCG;b) unusual life-threatening complication following infection caused by ordinary

benign viruses (e.g., giant rubella pneumonia; varicella pneumonia);c) chronic oral candidiasis after 6 months of life;d) chronic mucocutaneous candidiasis;e) fine, thin hair, short-limbed dwarfism with characteristic

radiographic features of cartilage-hair hypoplasia (CHH);f) intrauterine graft-versus-host disease - the most characteristic

feature is scaly erythroderma and total alopecia (absence of eyebrowsis quite striking);

g) graft-versus-host disease after blood transfusion;h) hypocalcemia in newborn (Di George anomaly, especially with characteristic

faces, ears and cardiac lesions); i) small (less than 10 mm in diameter) lymphocytes count persistently less than

1500/mm3, must rule out gastrointestinal loss of them or loss from the lymphatic vessels.

Diagnostic criteria of primary immunodeficient conditionsB. Suggestive R-cell defecta) recurrent proved bacterial pneumonia, sepsis or meningitis;b) nodular lymphoid hyperplasia.C. Suggestive B- and T-cell deficiency (combined immunodeficient

disease - CID)a) all the above mentioned features except chronic mucocutaneous candidiasis and

nodular lymphoid hyperplasia;b)features of Wiskott-Aldrich syndrome (draining ears, trombocyto-penia and

eczema);c) features of ataxia-telangiectasia.P. Suggestive immunodeficiency without clearly implicating T-or B-cell defecta) Pneumocystis carinii pneumonia;b) intractable eczema;c) ulcerative colitis in infants less than 1 year old;d) intractable diarrhea;e) unexplained hematological deficiency (RBC, WBC, platelet);f) severe generalized seborrheal dermatitis (Leiner's disease) suggests

C5 deficiency; seborrhea is common in combined immunodeficient disease;g) recurrent pyogenic infections seen in C3 deficiency.

Diagnostic criteria of primary immunodeficient conditionsE. Suggestive biochemical defecta) features of combined immunodeficiency with characteristic bony

lesions (adenosine deaminase deficiency);b) features of Blackfan-Diamond aplastic anemia (nucleoside

phosphorylase deficiency).F. Suggestive abnormality of polymorphonuclear leukocytesa) primary skin infections (if associated with asthma, eczema and

coarse faces, think of Buckley syndrome);b) chronic osteomyelitis caused by Klebsiella or Serratia species,

draining lymph nodes (chronic granulomatous disease).G. Suggestive secondary deficiencya) concomitant or preceding viral infection;b) lymphoid malignancy (chronic lymphatic leukemia, Hodgkin's

disease, myeloma).

Diagnostic criteria of primary immunodeficient conditionsLaboratory:a) genealogical anamnesis;b) common blood analysis (not only total but absolute quantity

of different leukocytes);c) investigation of numeral link of immunity: gamma globulin concentration; immune serum globulins by Manchini; Immunoelectrophoresis of serum proteins; tillers of different antibodies, blood group, liter of isohemagglu-tinins; secretory immunoglobulins; surface immunoglobulins of antiserum lymphocytes, marked with fluoroscein; EAC-rosellas.d) investigation of cellular link of immunity: E-rosellas; reaction of blast transformation (in unspecific stimulation with FHA, in stimulation with

antigens, in mixed lymphocyts culture); depression of macrophages migration; reaction of hypersensitivity of a delayed type (intracuta neous tests with 2,4-

dinitroftorbenzol, streptokinase, odoriase, antigen; Shieck's reaction).

Diagnostic criteria of primary immunodeficient conditionse) special investigations: functions of T-helpers and T-suppressors; hystochemical determination of adenosine-deaminase's activity; transcobalamin's content. X-ray of the chest including side positions and tomo-gram of

mediastinum for revealing the thymus; biopsy of the lymph nodes with the use of hystotogical and

hystochemical methods;h) investigation of complement's system (total complement, its

factors);i) investigation of phagocytosis function (opsonization bacteria's

killing, a test with blue tetrazolium, cytochemical methods of determination of enzyme's activity etc.)

Primary immunodeficient conditions. Primary immunodeficient conditions. Classification of primary immunodeficient Classification of primary immunodeficient

conditionsconditions1.1. Prevalence of antibodies deficiency:Prevalence of antibodies deficiency:a) sex-linked agammaglobulinemia;a) sex-linked agammaglobulinemia;b) sex-linked agammaglobulinemia and growth hormone b) sex-linked agammaglobulinemia and growth hormone

deficiency;deficiency;c) autosomal recessive agammaglobulinemia;c) autosomal recessive agammaglobulinemia;d) selective immunoglobulin deficiency:d) selective immunoglobulin deficiency: - with elevated level of IgM and IgD;- with elevated level of IgM and IgD; - IgA deficiency.- IgA deficiency.e) selective deficiency of other isotypes of Ig;e) selective deficiency of other isotypes of Ig;f) kappa-chains deficiency;f) kappa-chains deficiency;g)g) immunodeficiency on the background of thymoma;immunodeficiency on the background of thymoma;h)h) transitory hypogammaglobulinemia in children.transitory hypogammaglobulinemia in children.

Primary immunodeficient conditions. Primary immunodeficient conditions. Classification of primary immunodeficient Classification of primary immunodeficient

conditionsconditions2.2. Combined immunodeficiency:Combined immunodeficiency:a) total variable immune deficiency:a) total variable immune deficiency:with primary antibody deficiency;with primary antibody deficiency;with primary deficiency of cellular immunity.with primary deficiency of cellular immunity.b)b) severe combined immunologic deficiency:severe combined immunologic deficiency: - reticular dysgenesis;- reticular dysgenesis; -deficiency of T- and B-lymphocytes (earlier the Swiss type of IDC).-deficiency of T- and B-lymphocytes (earlier the Swiss type of IDC).c) T-lymphocyte deficiency (earlier Nezelof syndrome);c) T-lymphocyte deficiency (earlier Nezelof syndrome);d) adenosindeaminase deficiency;d) adenosindeaminase deficiency;e) purine-nucleotide-phosphorylase deficiency;e) purine-nucleotide-phosphorylase deficiency;f)f) absence of HLA-antigens of the 1st class (syndrome of "naked"absence of HLA-antigens of the 1st class (syndrome of "naked"

lymphocytes);lymphocytes);g)g) absence of HLA-antigens of the 2nd class.absence of HLA-antigens of the 2nd class.

Primary immunodeficient conditions. Primary immunodeficient conditions. Classification of primary immunodeficient Classification of primary immunodeficient

conditionsconditions

3. Immunodeficiency in combination with other 3. Immunodeficiency in combination with other congenital defects:congenital defects:

a) Wiscott-Aldrich syndrome;a) Wiscott-Aldrich syndrome;b) ataxia-telangiectasia (Louis-Bar, syndrome);b) ataxia-telangiectasia (Louis-Bar, syndrome);c) syndrome of 3nd-4,h pockets of branchial arch (Di c) syndrome of 3nd-4,h pockets of branchial arch (Di

George syndrome);George syndrome);d) transcobalamin-2 deficiency;d) transcobalamin-2 deficiency;e) mmunodeficiency due to congenital anomalous e) mmunodeficiency due to congenital anomalous

reaction at Epstein-Barr virus.reaction at Epstein-Barr virus.

Therapeutic management The only definitive treatment is a histocompatible bone marrow

transplant. The perfect donor is an identical twin because the human lymphocyte antigens (HLA) are exactly the same. The second best choice is a sibling. The procedure consists of aspirating several samples of bone marrow from the donor and infusing the marrow intravenously into the host. However, bone marrow transplants are usually done at medical centers where measures to control posttransplantation infection, such as a sterile environment, and other specialized facilities are available. Since the host's immunologic system is incompetent, graft rejection is not a problem. However, a graft-vs-host reaction is always a possibility in a nonidentical twin graft, and once it occurs, little can be done to reverse the process.

IMMUNISATIONProtection against some of the infectious diseases is available in

the form of immunization which is given at various stages during childhood. Immunizations for different diseases are scheduled tobalance the risks of disease with the child's ability to produce a good immunological response; Immunization should not be given if the child is acutely unwell or if a severe reaction has occurred to a previous dose of that vaccine. Live attenuated vaccines (e.g. poliomyelitis, measles, mumps, rubella, BCG) should not be given to children" with immune deficiency states including those on cytotoxic drugs and high doses of corticosteroids, because of the risk of severe generalised infection. Three weeks should elapse between live vaccines to ensure adequate immune responses to the second one.

National immunisation scheduleDerived from Salisbury DM, Begg NT 1996 Immunisation against infectious disease- Department of Health, HMSO, London

INFANT Birth BCG for babies in Asian and other immigrant families .with high TB rates and those in contact with active respiratory

tuberculosis 2 months Polio + diphtheria /tetanus/ pertussis (DTP) + Haemophilus influenzae B (Hib) 3 months Polio + DTP + Hib 4 months Polio + DTP + Hib 12-15 months Measles, mumps and rubella (MMR)PRE-SCHOOL 3-5 years Booster polio + diphtheria/tetanus (DT) + MMR 3 years after

primary courseSECONDARY SCHOOL 10-14 years BCG after tuberculin skin testSCHOOL LEAVING 15-19 years Polio + tetanus/diphtheria (Td) MMR if not received previously

Panhypogamma-globuliriaemia

This presents as recurrent sinopulmonary infection, recurrent otitis media, bronchiectasis or giardiasis infection. It may be 'early,onset' in the first two years, which is almost always the X-linked disorderdescribed by Bruton, or 'late onset' where the presentation is more variable and the inheritance pattern less certain. Failure to thrive, gastrointestinal disorders and autoimmune disorders may complicatethe clinical course. Gamma globulin replacement therapy often results in a dramatic improvement.

Selective IgA deficiency

This presents with recurrent upper and lower respiratory, and gastrointestinal tract infections. Low serum IgA levels are found inbetween 1 in 400 and 700 children, but the deficiency disorders only occur in around 1 in 15 000,: this subgroup having associatedabnormalities in IgG production. They too benefit-from gamma globulin administration.

T-cell deficiencies These conditions present with frequent and severe

infections with herpes simplex, measles, varicella, cytomegalovirus, Pneumocystis and fungi such as nocardia, Candida and aspergillus. T-cell deficiencies may be isolated or part of extensive immunodeficiency states in which humoral immunity is also impaired. Di George syndrome is an example of T-cell deficiency associated with congenital absence of the thymus. T-cell function is defective in Wiskott-Aldrich syndrome, ataxia telangiectasia and chronic mucocutaneous candidiasis. Bone marrow transplantation may be used to replace T-cell deficiencies, although it is of high risk especially in patients with a strong previous history of recurrent infections.

Severe combined immune deficiency

This presents with failure to thrive in the first year of life, - recurrent sinopulmonary infection, - persistent candidiasis,- Pneumocystis infections, - persistent diarrhea, - severe recurrent systemic infections- disseminated viral infections.

It is a rare condition and is inherited as autosomal recessive or X-linked. First cases in families are difficult to diagnose and almost, always have established infection. A low lymphocyte count (<2.8xl0*9) is an important clue worthy of further investigation. Subsequent pregnancies may be offered antenatal diagnosis and immediate postnatal investigation. Deficiency of adenine deaminase (ADA) or purine nucleoside phosphorylase (PNP) are found in certain subtypes. For children with severe combined immune deficiency (SCID) successful treatment depends upon the presence of an HLA matched bone marrow donor.

Complement (C 5,6,7 and 8) deficiencies In general deficiencies do not normally

present with recurrent infections but are found as a result of investigation of the immune system for other disorders, for example vasculitis. Recurrent neisseria infections can be a presenting feature because of the specific need for components of complement to clear-this group of organisms.

Chronic granulomatous disease

This presents as recurrent staphylococcal infections with abscesses in and around liver, lungs and bones, or. infection with uncommon organisms, or chronic lymphadenopathy and hepatosplenomegaly. Chronic granulomatous disease (CGD) is an X-Iinked disease in which phagocytes can ingest pathogens but are unable to mount the oxidative burst of intracellular metabolism necessary to kill them. It used to be fatal but continuous administration of antibacterial agents like trimethoprim together with vigorous antibiotic therapy for each new infection has improved the outlook in children diagnosed early and monitored closely.

Acquired immunodeficiency syndrome (AIDS)

AIDS is caused by human immunodeficiency virus (HIV) of type 1 (HIV-1). HIV-1 infects CD4+ T-lymphocytes predominantly. Depletion of CD4+ lymphocytes results in immunodeficiency.

The clinical picture of AIDS is the final phase of HIV infection and its manifestation, with a wide spectrum of clinical disorders. The majority of them is nonspecific.

Clinical manifestations of HIV infection in children Persisting generalized

lymphadenopathy

Persisting hepatomegaly

Persisting splenomegaly

Persisting diarrhea

One or more nodes have size more than 1 cm and exist longer uian 1 month (especially substantial is enlargement of auxiliary lymph nodes)

Enlargement of the liver, registered for 3 months and more

Enlargement of the spleen, registered for 3 months and more

Stool is three times a day for more than 1 month

Clinical manifestations of HIV infection in children Fever

Persisting enlargement of salivary glands

Thrombocytopenia

Serious bacterial infections

t = 38 CC for 4 weeks and more, 2 and more episodes of fever of obscure nature

For 3 months and more Amount of thrombocytes is

less than 100 000 per ml twice and more times

2 and more episodes of exacerbation or chronization of an infection (for more than 3 days in spite of the treatment)

Clinical manifestations of HIV infection in children Retardation of

development Persisting or recurring

oral candidiasis

Cardiomyopathy

Nephropathy

Progressing hypotrophy, encephalopathy

It lasts for 2 months and more or relapses after the course of treatment

Signs of heart insufficiency

Nephrotic syndrome (proteinuria, hypoalbuminemia)

CARE OF A CHILD WITH IMMUNODEFICIENT CARE OF A CHILD WITH IMMUNODEFICIENT CONDITIONSCONDITIONS

A report of certain communicable diseases A report of certain communicable diseases must be filed with the city health must be filed with the city health department upon the admission of the department upon the admission of the child.child.

Personnel giving direct care to the child with a Personnel giving direct care to the child with a communicable disease should seek communicable disease should seek protection when immunization measures protection when immunization measures are; available. Frequent handwashing is are; available. Frequent handwashing is essential.essential.

Isolation GownsIsolation GownsWhen isolation gowns are used, a fresh gown When isolation gowns are used, a fresh gown

should be used for each patient contact. should be used for each patient contact. Organization of activities is essential for the Organization of activities is essential for the economical use of supplies.economical use of supplies.

CARE OF A CHILD WITH CARE OF A CHILD WITH IMMUNODEFICIENT CONDITIONSIMMUNODEFICIENT CONDITIONS

Isolation MasksIsolation MasksIf a mask is used, it should cover both the nose and the If a mask is used, it should cover both the nose and the

mouth, be worn no longer than 30 minutes, and be mouth, be worn no longer than 30 minutes, and be discarded immediately after use. discarded immediately after use. Disposal of WastesDisposal of Wastes

Paper bags for the disposal of tissues should be Paper bags for the disposal of tissues should be available within the unit. All contaminated waste available within the unit. All contaminated waste should be wrapped securely and discarded in a should be wrapped securely and discarded in a special receptacle marked "isolation."special receptacle marked "isolation."

Bedpans may be emptied into the community sewage Bedpans may be emptied into the community sewage system, using the bedpan flusher. The flusher system, using the bedpan flusher. The flusher should be handled with paper barriers. Waste cans should be handled with paper barriers. Waste cans should be lined with paper and kept covered.should be lined with paper and kept covered.

All reusable equipment should be cleaned, wrapped, All reusable equipment should be cleaned, wrapped, labeled "isolation," and sterilized before routine labeled "isolation," and sterilized before routine reprocessing. Infusion bottles should be discarded reprocessing. Infusion bottles should be discarded after useafter use

CARE OF A CHILD WITH CARE OF A CHILD WITH IMMUNODEFICIENT CONDITIONSIMMUNODEFICIENT CONDITIONS

Care of DishesCare of DishesDisposable dishes maybe requested Disposable dishes maybe requested

through the dietary department. If through the dietary department. If regular dishes are used, they should regular dishes are used, they should be returned to the kitchen for be returned to the kitchen for processing in the dishwashing processing in the dishwashing machine. Formula bottles should be machine. Formula bottles should be washed and returned to the washed and returned to the reception area of the formula reception area of the formula kitchen.kitchen.