1. ATYPICAL HEMOLYTIC UREMIC SYNDROME : TREATMENT OPTIONS
Chantal Loirat, Hopital Robert Debré, Paris, France

2. aHUS IN CHILDREN FRENCH PEDIATRIC REGISTRY
90 children (onset before age 16), 82 pedigrees
46 boys, 44 girls
Sporadic HUS 68 (83 %), familial HUS 14 (17 %, 22 children)
CFH mutation 17 (19 %)
MCP mutation 13 (14 %)
CFI mutation (9 %)
C3 mutation (7 %)
CFB mutation (1 %)
Combined mutations (8 %) (CFI + either CFH, or MCP, or CBF, or
C3(2); MCP + C3 ; CFH + CFH)
Anti-CFH antibodies 10 (11 %)
Complement – HUS 62 (69 %)
Unexplained HUS 28 (31 %)

3. AGE AT ONSET 90 patients (French cohort)
CFH
J J12
CFI
J1 J18 J28
J358
MCP
CFB C3
Combined
I + B
I + C3
I + H
I + C3
H + H
I + MCP
MCP + C3
Anti
CFH Ab
8 m
3 y 6 m J1
Unexplained
52 %
3 m
1 y
4 y
12 y
16 y
Heterozygous
Homozygous

4. EXTRA-RENAL INVOLVEMENT 90 patients (French cohort)
Central nervous system
(seizures, coma, diffuse cerebral ischemia) 16 (18 %)
Multivisceral failure
Cardiorespiratory arrest
Pancreatitis/hepatitis

5. OVERALL RISK OF DEATH AND EVOLUTION TO END STAGE RENAL DISEASE 90 patients (French cohort)
DEATH 6 (7 %) (4 from CNS involvement, from pulmonary hemorrhage/ CRA,
1 from sepsis)
all during the first year after onset)
ESRD (42 %)

6. RELAPSING COURSE (from 1 to 9 relapses)
N (%) of patients with
relapses of HUS
CFH homozygous mutation n=4 3 (75 %)
CFH heterozygous mutation n=5 3 (60 %)
not in ESRD
MCP mutation n= (77%)
CFI mutation n=8 1 (12 %)
C3 mutation n=6 1 (17 %)*
CFB mutation n=1 1
Combined mutations n=7 5 (71 %) *
Anti-CFH antibodies n= (50 %)
Unexplained HUS n= (25 %)
* one additional child had chronic hemolysis/thrombocytopenia until bilateral nephrectomy

7. PROGNOSIS ACCORDING TO COMPLEMENT MUTATION French cohort
CFH (n=13)
C3 (n=6)
CFI (n=8)
MCP (n=13)
p=ns
CFI
Free of ESRD or death C3
p=ns
MCP
CFH
p=0.0003
Time (months)
At 1y
At 5y

8. PROGNOSIS OF aHUS WITH COMBINED MUTATIONS 7 patients French cohort
MCP
CFH
CFI 3
CFB C3
Free of ESRD or death
> 1mutation
MCP
CFH
CFH
CFH
Time (months) C3 +
MCP

9. PROGNOSIS IN THE « ORPHAN GROUP » COMPARED TO CFH AND MCP GROUPS French cohort
CFH (n=13)
MCP (n=13)
No mutation (n=28)
Free of ESRD or death
CFH
No mutation
MCP
p=0.02
p=0.04
Time (months)
At 1y
At 5y

10. PLASMATHERAPY IN aHUS WITH CFH MUTATION review in Loirat et al, Pediatr Nephrol Lapeyraque, Pediatr Nephrol children with homozygous CFH mutation, 6 children + 1 adult with heterozygous CFH mutation benefited from rescue and preventive plasmatherapy (follow-ups : 7 m to 6 y) Example from Davin, Pediatr Nephrol 2008
2 monozygotic twin sisters, HUS at 4 and 4.5 y
heterozygous S1191L mutation, SCR 20
First twin : PE with FFP, 40 ml/kg/day x 10 days → resolution of hemolysis
Screatinine 166 → 137 µmol/l
next 4 months : 5 FFP infusions,10 ml/kg, for each of 3 relapses
→ ESRD
Second twin : PE with FFP, 40 ml/kg/day x 21 → resolution of hemolysis
Screatinine 132 → 61 µmol/l
→ PE tapered to 40 ml/kg every 2 weeks
2 relapses treated successfully by daily PE x 7 days
follow-up 6 years, Screat 66 µmol/l
long-term PE therapy appears to have benefits over FFP infusions alone

11. HOMOZYGOUS CFH MUTATIONS RESPONSE TO PLASMATHERAPY 4 patients, French pediatric cohort
Year of HUS
Plasmatherapy
at the acute phase
Outcome
1994 – n = 2 (cousins) no
2*. 15 ml/kg weekly
relapse and ESRD at M9
successfull transplantation with FFP
10 ml/kg twice a month, x 7 y
preserved RF with FFP 15 ml/kg weekly x 4 y
plasma-resistant relapse at 4 y → ESRD
2003 and n = 2
3. FFP 10 ml/kg x 12
4. PE 60 ml/kg x 10
preserved RF with
FFP 10 ml/kg every 2 to 3 weeks, plasma-
dependent, x 5 y
FFP 10 ml/kg x 3 times a week, x 2 y
* published by Nathanson 2001, 2006 ; Larakeb 2008

12. Homozygous CFH mutation 3694-3697 del TAGA, SCR20
Hemofiltration
Homozygous CFH mutation del TAGA, SCR20
Girl born on Sept 8, 2006
3 times a week FFP infusion 10 ml/kg
Daily PE
450
400
350
300
250
200
150
100 50
oct-06
nov-06
déc-06
janv-07
févr-07
mars-07
avr-07
mai-07
juin-07
juil-07
août-07
sept-07
oct-07
nov-07
déc-07
janv-08
févr-08
mars-08
avr-08
mai-08
juin-08
juil-08
août-08
sept-08
20 sept-06
Creatinine (µmol/l)
multivisceral
failure
Hemoglobin (g/l)
Platelets (103/ml)

13. COMPLEMENT DYSREGULATION AS A CAUSE OF VASCULAR COMPLICATION : RESCUE BY PE Larakeb et al, Pediatr Nephrol 2007
HUS at 7 m
preserved renal function from age 4 to 9 y under weekly plasma infusions
plasma exchange-resistant relapse at age 9 y → ESRD
after 3 years on dialysis without plasmatherapy, sudden unilateral blindness with ischemic/hemorrhagic retinal lesions, rescued by daily plasma exchanges (60 mg/kg FFP) x 10 d, then 3 times a week
→ complete recovery after 4 weeks
One child with homozygous CFH mutation (Y899X, SCR15)

14. HETEROZYGOUS CFH MUTATION OUTCOME ACCORDING TO PERIODS AND TREATMENT MODALITIES 13 patients, French pediatric cohort
Year of HUS
Plasmatherapy *
at the acute phase
Outcome
n=10
no 10/10
ESRD or death within < 1 year 9/10
n = 3
yes 3/3
1. FFP 10 ml/kg x 3 weekly
2. PE (FFP) 60 ml/kg daily x 15
3. FFP 10 ml/kg x 3 weekly
no renal sequelae 3/3
FFP 10 ml/kg weekly (plasma-dependent) x 1 y
PE (FFP) 60 ml/kg weekly (plasma-dependent) x 2.9 y
FFP 10 ml/kg monthly (no relapses) x 4 y
* defined as FFP ≥ 10 ml/kg or PE with FFP ml/kg, x ≥ 5 days

15. Heterozygous CFH mutation W1189R, SCR20 Weekly PE, 60 ml/kg FFP
Girl born on Aug 2005
Heterozygous CFH mutation W1189R, SCR20
Weekly PE, 60 ml/kg FFP
Weekly FFP infusion, 10 ml/kg
Daily PE
300
250
fever
fever
fever
200
150
100 50
déc-05
janv-06
févr-06
mars-06
avr-06
mai-06
juin-06
juil-06
août-06
sept-06
oct-06
nov-06
déc-06
janv-07
févr-07
mars-07
avr-07
mai-07
juin-07
juil-07
août-07
sept-07
oct-07
nov-07
déc-07
janv-08
avr-08
mai-08
juin-08
juil-08
févr-08
mars-08
Creatinine (µmol/l)
Hemoglobin (g/l)
Platelets (103/ml)

16. aHUS WITH MCP MUTATION EFFECT OF PLASMATHERAPY
Italian Registry*
(Caprioli et al, 2006)
14 patients
French pediatric cohort**
13 patients
N episodes
Treated
n=23
Untreated
n=12
n=37
Remission 21
(91 %) 12
(100 %) 11
(92 %) 35
(95 %)
* Italian cohort : FFP ml/kg/day and/or PE ml/kg, for a total of 2-36 treatments in 2-6 weeks ;
hematological normalization with or without renal sequelae
** French cohort : PE ml/kg x ≥ 4, hematological normalization and no renal sequelae

17. UNEXPLAINED HUS OUTCOME ACCORDING TO TREATMENT 28 patients (French cohort)
treated*
n = 12
not treated
n = 16
Outcome**
poor 7
(58 %)
favourable 5
(42 %)
poor 5
(42 %)
favourable 8
(50 %)
* FFP 10 ml/kg x ≥ 4 d (n = 4)
PE with FFP ml/kg x ≥ 4 d (n = 8)
** poor : death, ESRD, CRI ; favourable : no sequelae or mild proteinuria

18. aHUS : PLASMATHERAPY (1)
In practice : what should be done at admission ?
« Guideline for initial therapy », European Pediatric Study Group for HUS
in press, Pediatr Nephrol 2008
When to start ?
- as soon as possible (within 24 h)
as soon as the patient’s condition allows it (BP, volemia, hydroelectrolyte
equilibrium, anemia…)
- question : even if serum creatinine not elevated ?
yes, because :
* approximately 50 % of HUS with CFH mutation go to ESRD
at the 1st episode
* delay in treatment initiation can be deleterious in HUS with
anti-CFH antibodies

19. (2)
(2) Which volume ?
- Exchange 1.5 plasma volume (60-75 ml/kg) with FFP for restitution
- If PE is impossible, infuse FFP ml/kg (if BP and cardiac function OK)
(3) Which frequency during the first month ?
- daily x 5 days
- 5/week x 2 weeks
- 3/week x 2 weeks
(4) What are the situations which allow not to do PE or to stop early ?
- MCP mutation (PE only during relapses ?)
(5) Which frequency after the 1st month ?
empirical : try to find the threshold dose (PE or FFP infusion) and interval for each individual patient

20. aHUS TREATMENT THE TRIGGERING EFFECT OF INFECTIONS (upper respiratory tract infection, fever, gastroenteritis)
CFH CFI MCP C3 No
mutation mutation mutation mutation
Caprioli / / / /66
(69 %) (60 %) (100 %) (70 %)
French pediatric cohort 7/ / / / /28
(41 %) (62 %) (75 %) (80 %) (75 %)
Eradicate adenoïdal, tonsils, dental infections
Triggering effect of vaccinations documented in some patients : benefit probably outweighs the risk → perform vaccinations, including influenza
Intensify preventive plasmatherapy during infections and vaccinations (at least intensify biological monitoring)
In patients with permanent activation of the alternative pathway and very low C3 : preventive antibiotics and vaccination against Neisseria meningitis and Streptococcus pneumoniae

21. aHUS ASSOCIATED WITH ANTI-CFH ANTIBODIES 10 patients (French pediatric cohort)
Treatment at the acute phase
none 2 (retrospective diagnosis)
FFP infusions only 1
PE 7
+ steroïds 5
+ immunosuppressors 4 (aza 2, MMF 1, rituximab-cyclophosphamide 1)
Relapses (2 to 3) 5
Outcome
ESRD 2 (1 untreated, 1 delayed treatment)
HT/proteinuria/GFR (1 untreated, 4 treated)
no sequelae 3 (treated)

22. PROGNOSIS IN PATIENTS WITH ANTI-CFH ANTIBODIES COMPARED TO PATIENTS WITH CFH MUTATION French Cohort
CFH (n=13)
Anti CFH Ab (n=10)
Anti CFH Ab
p=0.01
Free of ESRD or death
CFH
Time (months)
At 1y
At 5y

23. 3 year-old boy Before PE After PE Anti-FH titer(AU/ml) PE Dialysis
IvIg
Corticotherapy
Azathioprine
D15 M2
Relapse 1 M6 M7
Relapse 2
M13
M15
M17
Relapse 3
M23
M27
M30
M44
M48
M54
D-15
Diarrhea
Onset
No renal sequelae at M54
H. Nivet, Tours

24. Corticosteroid therapy
11 year old boy
Anti-FH titer(AU/ml)
Plasma Exchanges
Corticosteroid therapy
+ azathioprine
FFP
Dialysis
RBC transf M2 M3 M6 M7 W3 M1
Onset
J.L. André, Nancy
B. Ranchin, Lyon

25. IgG anti-FH (AU) 7 y old girl HUS Apr 12, 2007
18 PE
Steroïds
May 2008
MMF
Sept 2008
11 RBC transf
Hematological normalization within 2 weeks
Renal function normalization within 2 weeks
J.L. André, Nancy

26. D-HUS WITH ANTI-CFH ANTIBODIES PREPARATION TO TRANSPLANTATION AND POST-TRANSPLANT COURSE Kwon T, 2008
500
1000
1500
2000
2500 C3
anti CFH Ab
months
transplantation
prednisone
+ azathioprine
FFP
PEX
mg/l
AU/ml
Hemodialysis
rituximab
prednisone + cyclosporine
+ mycophenolate mofetil
graft biopsy
no TMA
no rejection
Creatinine
85 µmol/l

27. Number of patients transplanted within year after recurrence
POST-TRANSPLANT RECURRENCE IN aHUS PATIENTS GENOTYPED FOR CFH, CFI AND MCP Retrospective studies Review in Loirat and Fremeaux-Bacchi, Pediatr Transplant 2008
Mutation
Number of patients transplanted
Recurrence
(% patients)
Graft failure for recurrence
within year after recurrence
(% of recurrences)
CFH 34
81 %
CFI 8
100 %
MCP 10
1/2
No mutation in
CFH, CFI or MCP 20
83 %
76 %
88 %
20 %
30 % 27

28. POST-TRANSPLANT RECURRENCE IN PATIENTS WITH NO MUTATION IN CFH, CFI, MCP, CFB AND C3 AND NO ANTI-CFH ANTIBODIES French pediatric cohort
7 transplantations in 5 children*
→ 2 graft loss due to thrombosis (1) and rejection (1)
→ no recurrence of HUS
* including one familial form of HUS

29. PLASMATHERAPY TO PREVENT POST-TRANSPLANT RECURRENCE IN 2 CFH-MUTATED SIBLINGS
EFFICACY OF PLASMA EXCHANGES WITH FFP STARTED BEFORE RENAL TRANSPLANTATION Olie, AJKD 2005; Davin, Pediatr Nephrol 2008
CFH heterozygous S1191L mutation, SCR 20)
Older sister Tx1
Tx2
Twin 1
Prophylactic PE
PE before surgery
daily PE X 7
weekly PE X 2 months
then PE 1 /2 weeks no
yes
Relapses
day 2
no treatment
Screat 80 to 200 µmol/L when PE 1/2w
PE 5 days later
M10 and M12(CMV)
daily PE then weekly
Outcome
graft loss
Screatinine 127µmol/L at 5 y

30. Graft loss within the year after recurrence
THE RISK OF RECURRENCE AFTER RENAL TRANSPLANTATION IN ADULT PATIENTS French adult cohort Transplantations performed after year 2000
Mutation
N patients
transplanted N
grafts
Recurrence
(% grafts)
Trt of recurrence
Graft loss within the year after recurrence
CFH 17 18
(2 with preventive plasmatherapy)
14 (78 %)
(1 treated preventively)
PE 11/14
10/14 (71 %)
CFI 8 9
(2 with preventive
plasmatherapy)
4 (44 %)
(no prevention)
PE 4/4
(follow-up 1 to 4.2 y) C3 6
(1 with preventive plasmatherapy)
5 (62 %)
PE 5/5
4/5 (80 %)
1 PE-dependent
1 y after recurrence B 1

31. aHUS WITH CFH MUTATION LIVER (n = 2) AND LIVER + KIDNEY (n = 10) TRANSPLANTATIONS
INITIAL EXPERIENCE WITHOUT PREOPERATIVE PLASMATHERAPY
(Remuzzi 2002, 2005 ; Cheong 2004)
3 children → 3 deaths (2 with diffuse thrombotic/ischemic liver lesions, 1 PTLD)
SUCCESS OF COMBINED LIVER + KIDNEY TRANSPLANTATION
UNDER PLASMATHERAPY BEFORE AND DURING SURGERY
(Saland 2006 ; Jalanko 2008)
3 children
PE with FFP, 1,25 to 2 plasma volume (50 to 100 ml/kg) just before surgery
FFP infusion (20 to 36 ml/kg) during surgery or PE (70 ml/kg) between
liver and kidney transplantation
+ post operative anticoagulation
→ excellent function of both grafts at 8 m, 15 m and 4 y follow-up
+ 5 children (unpublished) : 4 combined tx → 3 success,1 death (1/7 = 14 %)
1 liver tx → success
(+ 1 adult, combined tx → success )

32. aHUS INDICATIONS OF COMBINED LIVER + KIDNEY OR LIVER TRANSPLANTATION IN Consensus Conference, Bergamo, Dec 13, 2007
CFH MUTATION
Consensus + : - patient who lost a 1st graft due to recurrence
- patient with a family member with the same mutation who lost a graft due to recurrence
- patient with a mutation reported in the litterature or registries ( as associated with recurrence after transplantation
- in such cases, liver transplantation has to be considered when renal function is preserved by plasmatherapy
CFI MUTATION
Same recommendations as for HUS mutation (debatable for isolated CFI mutations)
CFB OR C3 MUTATION
Too early to give recommendations

33. PATIENTS FOR WHOM ISOLATED KIDNEY TRANSPLANTATION IS RECOMMENDED Bergamo Conference (2)
Patients with MCP mutation
Patients without identified mutation in CFH, CFI, CFB and C3
Patients with "low risk" CFH, CFI and C3 mutations : same mutation in a family member, a patient in the litterature or registries, without post-transplant recurrence
Except for patients with MCP mutations, intensive plasmatherapy (PE) started just before surgery is recommended

34. aHUS Treatment for the future
CFH concentrate (LFB Laboratory)
- 1st trials : end of 2009
- 1st candidates : patients with total or partial CFH deficiency
- respective place of PE and CFH concentrate to be evaluated in
the other patients with functionnal CFH deficiency
(2) COMPLEMENT BLOCKERS
- near future : anti-C5 monoclonal antibodies : eculizimab
- other options in development

35. ECULIZUMAB IN aHUS Preliminary data (with permission of physicians and Alexion)
J. Nuernberger et al (Essen)
- One adult, aHUS, Y475S CFH mutation
* 1st transplant : loss after recurrence
* 2 nd transplant : recurrence, resistant to 4 PE
→ 1 injection of 600 mg eculizumab → remission, normalization of graft function
follow-up : 5 months
B. Hurault de Ligny et al (Caen)
- One woman, aHUS with C3 mutation (R570Q)
* 2nd transplant, Jan 2004 : several recurrences, responsive to PE
May 2008 : recurrence, PE-dependent.
Switch to eculizumab (protocol as for PNH) → remission maintained.
Follow-up : 2 months.

36. CONCLUSION
Although evidence from therapeutic trials is lacking, early plasmatherapy, best by PE, remains first line treatment to rescue aHUS, especially in patients with CFH mutation or anti-CFH antibodies. Long-term plasmatherapy also appears efficient to prevent relapses in patients with CFH mutation.
Liver transplantation, isolated or combined with kidney transplantation, has to be discussed on a case by case basis for patients with mutations of complement factors synthetized in the liver. The decision remains difficult.
We are at the crossing of roads, as new therapies, such as eculizumab or other complement inhibitors, and CFH concentrate, will soon be evaluated. Hopefully, these new therapeutics will allow that aHUS will no longer end-up in ESRD and the discussion of liver or combined liver + kidney transplantation might become obsolete.

37. THANKS TO
Veronique FREMEAUX-BACCHI and the group of the Laboratory of Immunology, Hopital Européen Georges Pompidou
Marie-Agnès Dragon-Durey
Jacques Blouin
Lubka Roumenina
Christophe Hue
Arnaud GARNIER, Hopital Robert Debré
The members of the French Society of Pediatric Nephrology
The patients and their families
The Association pour l'Information et la Recherche sur les Maladies Rénales Génétiques (AIRG) and the Programme Hospitalier de Recherche Clinique