الفهرس 
Materials and methodsOnly 14 pages are availabe for public view
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Abstract
Saprophytic and non-pathogenic streptococci are widely
distributed in nature, but some species are pathogens for
human being, among of which are, group A, beta-hemalytic
streptococci which are common in sore throat of children.
This infection is usually of short duration but it always
produce delayed acute post streptococcal glomerulonephritis.
Acute post-streptococcal glomerulonephritis (AGNl is a form
of acute glomerular injury which is a delayed sequela of
infection with certain nephritogenic strains of group A Bhemolytic
streptococci. Documentation of streptococcal infection
(positive throat culture or elevated tit res of antibody
to certain extracellular antigens such as stryptolysin 0 is
an important factor for establishing the diagnosis.
The urinalysis usually reveals pr ot ei nur ia, hematuria,
and the presence of red blood cell casts. Hypertension,
azotemia, and aliguria are usually mild but may be severe in
a small percentage of patients. AGN is generally a nonprogressive
disease in children leading to complete recovery
(Baldwin et ai., 1974).
Many morphological, clinical, and serological features
suggest that acute poststreptococcal glomerulonephritis
(APSGN)is an immune complex disease (Glassock e tal., 19B6).
Frequently following the onset of this disease, serum C3
levels are markedly depressed. Discrete deposits of IgG and
C3 on the epithelial side of the GBM have been detected. In
addition, soluble immune complexes have been detected in the
circulation of some patients with AGN (Mohammed et al., 1977;
Ooi et al., 1977).
Up till now, no specific genetic marker is characteristic
for post-streptococcal glomerulonephritis in Egypt. As
striking relationship have been found between HLA-antigen and
many diseases, the present work was undertaken to look for
any association between (PAGN) and certain alleles of the
HLA-A,B,C and DR.
The present work included 33 patients, 19 males and 14
females with ~ge ranged from 4-14 years. They were taken up
consecutively from the inpatients of the Department of Pediatrics
at Mansoura University Hospital.
The cases were presenting clinically and laboratory as
acute glomerulonephritis, post-streptococcal on the basis of
presence and/or history of sore throat, or pyogenic skin
infection, and evidence of streptococcal infection.
For all members included in the study, the following
were done:
- Full detailed history.
_ Laboratory investigations .
• Culture of skin infection and throat swabs, and serological
grouping of isolated streptococci by:
1) Streptex test
2) Bacitracin sesnitivity test.
* Urine analysis
_ Chemical and serological investigations.
* serum creatinin, creatinin clearance serum electrolytes
to evalute kidney function.
* C-creactive protein and A.S.O titre.
* Identification of serum (Igs), complement and CIC.
* HLA tissue typing.
In the present study, throat swabs were taken from 33
cases of acute glomerulonephritis. Beta-hemolytic streptococci
were identified by the presence of beta-hemolysis on
blood agar plates. The number of beta-hemolytic streptococcal
isolates was 7 in all 33 cases. These isolates were
grouped by streptex kits, bacetracin sensitivity disks. The
number of group A beta-hemolytic streptococci identified by
streptex was 7 (100%) of the isolated cases. The number of
group A identified by bacitracin disks was 6 out of 7 seven
cases (85.7%). from the previous data, it is quite clear
that the incidence of group-A beta-hemolytic streptococcal
isolates is low. The sensitivity of streptex kits in identificaiton
of group A streptococci was striking, but bacitracin
disks was less sensitive.
The antistreptolysin 0 titre was determined by the
latex method. The mean value of antistreptolysin 0 titre was
higheL in cases fLom which beta-hemolytic stLeptococci weLe
isolated than in cases fLom which no beta-hemolytic stLeptococci
weLe isolated. The mean value of ant i st rep t oLya Ln 0
titLe was (742.86 & 384.62) Lespectively C-Leactive pLotein,
was found to be positive in all cases of acute PoststLeptococcal
glomeLulonephLitis.
HLA antigens weLe typed by using the micLolymphocytoxicity
tissue typing technique (BoLdmeL, 1978).
The HLA-B8 1S the only antigen in locus B that shows
significantly higheL fLequency compaLed to contLols because
its fLequency in the patient (42%)
compa red to no rma L con t roIs (6.5%)
is significantly high
and P(O.OOl. Also the
Lelative Lisk is high and significant (RR = 10.6). FULtheLmOLe
the contLibution of the antigen as measuLed by etiologic
fLaction is high 0.684.
Statistical analysis also Levealed that the only significant
diffeLence of HLA-DR is that between the fLequencies of
HLA-DR3. The DR3-antigen fLequency in the patients (27.3%)
compaLed to that of contLol (14.9). The RR = 7.14. FULtheLmo
re , the test of significance of the RR (total X 2) shows
significance RR. P(O.OOl.
- Assays fOL ciLculating immune complexes by lazeL nephelome
t ry were positive and mo re than 1.5 mg/dL fOL every
patient which indicated antigen antibody Leaction fOLming the(222)
immune complexes in all patients.
The level of C3 measured by lazer nephelometry was found
decreased in 23 out of 33 cases. The means of C3 and C4
levels were consequently the following, 51.838 and 32.65. C3
was present with seven cases having HLA-B8 and decreased in 6
out of these 7 cases while was decreased in 4 out of 6 cases
having HLA-DR3 haplotype, and was decreased in all the six
cases having HLA B8/DR3. This indicated that there is a
great association of both C3 and HLA B8 as well as B8/DR3
hawlotypes in APSGN
Serum levels of IgG were below the normal level in 28
out of 33 cases.
IgG was decreased in seven cases out of eight, havin~
HLA-B8 and with 5 out of 6 having HLA-DR3. This indicates
that there is a great association of the IgG and HLA-B8 as
well as HLA-DR3 in APSGN.
_ In contast, the IgA, was decreased in only one case
out of six with B8, two cases out of six with DR3 and three
cases out of six with B8 DR3. This indicated that IgA is not
associated with any genetic factor in APSGN. Also there is insignificant correlation between the
leve Ls of IgM and HLA-haplotypes, however the mean of IgM in
our patient (301.3) was high than that of control (164.2).