Results:
Forty children were screened at enrolment. 5 children were excluded (1-
diagnosed to have malignancy; 2 children- blood culture positive with
DIC; 2 children- parents not giving consent). 35 children who fulfilled
the inclusion criteria were enrolled and were further investigated.
Median age was 49 months with IQR of 9 to 90 months. The highest age
noted was 140 months while the lowest, 1 month. Majority of patients
were more than 24 months (60%). Out of 35 children studied, 62.9% were
males with a sex ratio of 1.7: 1. While decreased urine output was the
most common presentation, pallor was the most common clinical finding.
(Table 1) Details of symptoms at presentation are described in Figure 1.
Severe anemia was noted in 88.6% (31) and severe thrombocytopenia in
71.4% (25). AKI Stage 3 was seen in 80% (28) at presentation though
91.4% (32) developed it during the course. Hematuria was observed in
59.9% (21) children, among which 2 children had gross hematuria.
Proteinuria was present in 27children, out of which 12 (34.3%) had
nephrotic range. Six out of twelve children who showed a diarrhoea
prodrome had their stools evaluated for STEC PCR to rule out STEC HUS,
which were negative. Thirteen children had positive ANA (speckled
pattern). Among those with positive ANA, ds-DNA was done in 3 children
which were normal.
C3 and C4 levels were analyzed in all 35 patients among whom 57.1% (20)
had low C3 and 25.7 % (9) had low C4 levels. Both C3 and C4 levels were
low in 6 children. Five children who had low C3 and C4 were also
negative for ANA, but one had speckled pattern ANA positivity. Mean C3
and C4 levels were 75 ± 26 mg/L and 22 ± 8 mg/L respectively. Three
children had low FH levels with no relation to anti-FH antibody. Two
children had low FI levels while 3 children had high FB levels. Anti-FH
antibody levels were elevated in 44% (15) of children with a mean
anti-FH titre level of 137.68 ± 50.1 AU/ml. Low CD46 expression assessed
by median fluorescent index in neutrophils, monocytes and lymphocytes
was noted in 8 children. (Mean δMFI - 8311 ± 1415.5) [Figure 2]
25 children had hypertension that was controlled with a mean of 3
anti-hypertensive drugs. 7 of them exhibited hypertensive emergencies
requiring parenteral anti-hypertensive drugs. 62.8% (22) required
dialysis support. Plasmapheresis (PEX) was offered to all children and
plasma infusion was tried in the very small infants where PEX was not
feasible. PEX was performed in 16 children while plasma infusion was
given in 7. Immunosuppression was initiated in children where
possibility of anti-FH antibody HUS was considered. Most of these
children were those who had already received plasma therapy.
Seventeen children (48.6%) improved in terms of hematological remission
with or without renal improvement. Eighteen children (51.4%) had a
negative outcome as death or withdrawal of care (lost to follow up).
On further analysis, younger children (less than 24 months) had more
negative outcome (36.8%) than those more than 24 months (63.2%)
(p< 0.05). The mean hemoglobin levels were always on a higher
side among children who had later attained remission compared to those
who did not, however it was not statistically significant.