Lipid and hemolysis parameters predicting acute chest syndrome in adulthood with sickle cell disease.

Sickle cell disease (SCD) is a lifelong blood disorder affecting approximately 100,000 people in the United States and is one of the most common monogenic diseases. A serious complication of SCD is acute chest syndrome (ACS). ACS is a condition with a high rate of morbidity and mortality. The aim of the study was to assess hemolysis and lipid parameters in a cohort of confirmed SCD patients to predict ACS development in the following year.Standard lipid were performed (triglycerides, total cholesterol, high-density cholesterol, low-density cholesterol) panel to calculate of non-HDL-C, large buoyant LDL cholesterol (lbLDL-C) and small dense LDL cholesterol (sdLDL-C) with Sampson equation. Hemolysis and hematologic parameters were also evaluated.Among 91 patients included between September 2018 and June 2021, thirty-seven patients had history of ACS and 6 patients developed ACS during following year. In unadjusted logistic regression, total bilirubin was associated with ACS occurrence (RR: 1.2 [1.05-1.51] p = 0.013). Concerning lipid profile, non-HDL-C (RR: 0.87 [0.0.67-0.99] p = 0.04) and sdLDL-C (RR: 0.78 [0.49-0.96] p = 0.03) were associated with ACS occurrence decrease. C-reactive protein was associated with ACS occurrence (RR: 1.27 [1.065-1.85] p = 0.011).Based on these findings, this study demonstrated that several biomarker easily available can be used at steady state to predict ACS in the following year. The validation of these results are required to ensure the reproducibility of the findings.

Pubertal development of transfusion-dependent thalassemia patients in the era of oral chelation with deferasirox: results from the French registry.

Not available.

Oncological and endocrinological outcomes for children and adolescents with testicular and ovarian sex cord-stromal tumors. Results of the TGM13 National Registry.

RATIONALE: Sex cord-stromal tumors (SCST) are hormonally active and rare. The aim was to describe their endocrinological presentation and outcomes. METHOD: Patients (< 19 years) registered in the TGM13 registry between 2014 and 2021 for SCST were selected. RESULTS: Sixty-three ovarian SCST (juvenile granulosa tumor (JGT) n = 34, Sertoli-Leydig cell tumor (SLCT) n = 17, other SCST n = 12) were included. Median age was 13.1 years (0.4-17.4). Germline DICER1 pathogenic variant was present in 9/17 SLCT. Sixty-one were FIGO stage I (IC n = 14). Adjuvant chemotherapy was administered for 15. Seven had recurrence (FIGO IA n = 3, IX n = 2, III n = 2), leading to one death. With a median follow-up of 42 months (2.5-92), the 3-year progression-free survival (PFS) was 89% (95% CI 76%-95%). Median age was 6.4 years (0.1-12.9) among the 15 testicular SCST (Leydig cell tumor n = 6, JGT n = 5, Sertoli cell tumor n = 3, mixed SCST n = 1). Tumor-nodes-metastases (TNM) stage was pSI in 14. Eight underwent a tumorectomy, 7 an orchiectomy. None experienced recurrence. Endocrinological data were reviewed for 41 patients (18 prepubescent). Endocrine symptoms were present at diagnosis in 29/34 females and 2/7 males (gynecomastia). After a median follow-up of 11 months, 15 patients had persistent endocrine abnormalities: gynecomastia/breast growth (2 males, 1 prepubescent female), precocious/advanced puberty (4 prepubescent females), and hirsutism/menstruation disorders/voice hoarseness/hot flashes (8 pubescent females). The mean height at the last follow-up was within normal ranges (+0.3 standard deviation). CONCLUSIONS: SCSTs have a favorable prognosis. Tumorectomy appears safe with testicular primary. Endocrinological disorders, common at diagnosis, may persist warranting endocrinological follow-up.

Lactate dehydrogenase and hemolysis index to predict vaso-occlusive crisis in sickle cell disease.

Sickle cell disease (SCD) is an inherited hemoglobinopathy disorder associated with chronic hemolysis. A major complication is vaso-occlusive crisis (VOC), associating frequent hospitalization, morbidity and mortality. The aim of this study was to investigate whether hemolysis biomarkers were able to predict VOC risk in adult patients with SCD requiring hospitalization within 1 year. This single-center prospective study included adult patients with SCD at steady state or during VOC. A total of 182 patients with SCD were included, 151 at steady state and 31 during VOC. Among the 151 patients at steady state 41 experienced VOC within 1 year (median: 3.0 months [2.0-6.5]). We observed an increase of lactate dehydrogenase (LDH) (p = 0.01) and hemolysis index (HI) (p = 0.0043) during VOC compared to steady state. Regarding patients with VOC requiring hospitalization, LDH (p = 0.0073) and HI (p = 0.04) were increased. In unadjusted logistic regression, LDH > median (> 260 U/L) (RR = 3.6 [1.29-10.88], p = 0.0098) and HI > median (> 8 UA/L) (RR = 3.13 [1.91-5.33]; p < 0.001) were associated with VOC. The association of LDH > 260 U/L and HI > 12 UA/L presented a sensitivity of 90%, and a specificity of 72.9% to predict VOC. The association of LDH and HI cut-off was able to predict VOC risk in SCD.

Extracranial germ cell tumours in children and adolescents: Results from the French TGM13 protocol.

BACKGROUND: Chemotherapy for non-seminomatous germ cell tumours (NSGCT) exposes to dose-dependent toxicities. The TGM13-NS protocol (EudraCT 2013-004039-60) aimed to decrease the chemotherapy burden compared to the previous TGM95 protocol while maintaining the 5-year event-free survival (EFS) at 80% or more. PROCEDURE: Patients less than 19 years of age with disseminated NSGCT were enrolled (May 2014 to May 2019) and stratified into four groups: two intermediate-risk (IR: localised tumour with low tumour markers [TM]) groups treated with VBP (vinblastine-bleomycin-cisplatin): three courses for IR1 (ovarian tumour any age/testis tumour less than or equal to 10 years) and four courses for IR2 (extragonadal tumour 10 years or less) groups, and two high-risk (HR: metastatic and/or high TM) groups treated with etoposide-cisplatin and either ifosfamide (VIP) or bleomycin (BEP): three courses for HR1 (ovarian tumour any age/testis tumour less than or equal to 10 years and low TM/testis tumour more than 10 years and very low TM) groups and four courses for HR2 (remainder) groups. RESULTS: One hundred fifteen patients were included: median age of 12.8 years (0.4-18.9); tumour sites: 44 ovaries, 37 testes and 34 extragonadal. The 5-year EFS and overall survival (OS) were 87% (95% CI: 80-92) and 95% (89-98), respectively (median follow-up: 3.5 years, range: 0.2-5.9), similar to those of the TGM95 protocol (5-year EFS 89% (84-93), 5-year OS 93% (89-95), p = .561). The 5-year EFS were 93% (95% CI: 80-98), 88% (71-95) and 79% (62-90) for ovarian, testicular and extragonadal tumours, respectively. The 5-year EFS varied (p = .02) according to the risk groups: 90% (66-97), 64% (30-85), 95% (72-99) and 87% (74-94) for IR1, IR2, HR1 and HR2, respectively. TM decline adjusted to tumour site, and alpha-fetoprotein (AFP) level revealed a prognostic impact of time to normalisation on EFS: HR = 1.03 (1.003-1.007). CONCLUSION: Risk-adapted and globally decreased chemotherapy burden maintains excellent outcomes, exclusive of the IR2 group, which warrants more intensive chemotherapy.

Investigation of thrombin generation assay to predict vaso-occlusive crisis in adulthood with sickle cell disease.

Introduction: Sickle cell disease (SCD) is an inherited hemoglobinopathy disorder. The main consequence is synthesis of hemoglobin S leading to chronic hemolysis associated with morbidity. The aim of this study was to investigate Thrombin Generation Assay (TGA) to assess hypercoagulability in SCD and TGA parameters as biomarkers of vaso-occlusive crisis (VOC) risk and hospitalization within 1 year. Materials and methods: We performed TGA in platelet poor plasma (PPP) with 1 pM of tissue factor and 4 µM of phospholipid-standardized concentration, in duplicate for patients and controls. We measured thrombomodulin (TM), soluble endothelial Protein C Receptor and Tissue Factor Pathway Inhibitor (TFPI). Results: A total of 113 adult patients with SCD, 83 at steady state and 30 during VOC, and 25 healthy controls matched on age and gender were included. Among the 83 patients at steady state, (36 S/S-1 S/ß0, 20 S/Sα3.7, and 19 S/C-7 S/ß+) 28 developed a VOC within 1 year (median: 4 months [2.25-6]). We observed an increase of peak and velocity associated with a shortening of lagtime and time to peak (TTP) and no difference of endogenous thrombin potential (ETP) in patients compared to controls. TFPI (p < 0.001) and TM (p = 0.006) were significantly decreased. TGA confirmed hypercoagulability in all SCD genotypes and clinical status. The association of ETP > 1,207 nM.min and peak >228.5 nM presented a sensitivity of 73.5% and a specificity of 93.9% to predict VOC development within 1 year. Conclusion: We have demonstrated a hypercoagulable state in SCD associated with chronic hemolysis. These preliminary findings suggest that TGA parameters, as ETP and peak, could be used to predict VOC development within 1 year.

Could Aberrant Migration Explain Metachronous Germ Cell Tumors?

BACKGROUND: Extragonadal germ cell tumors (GCTs) are thought to arise as a result of local transformation of primordial gonadal cells (PGCs) that become misplaced during embryogenesis. With the exception of bilateral testis tumors, metachronous GCT (i.e., occurring at a site classically described for primary GCTs) are rare events. PATIENTS AND METHODS: The clinical, radiological, and molecular data (if available) of patients with metachronous GCT were analyzed. RESULTS: Three Caucasian males were identified: case 1 presented with a pineal germinoma 19 years after a mediastinal seminoma that had been treated with chemotherapy, case 2 presented with a pineal non-seminomatous GCT (NSGCT) that occurred three years after a mediastinal seminoma treated with chemotherapy, and case 3 presented with a mediastinal seminoma concomitant with a suprasellar germinoma that occurred two years after a stage I testicular NSGCT treated exclusively with surgery. None of these patients had a positive family history or disorder of sex development. Molecular data were available for cases 2 and 3. In case 2, a CHEK2 gene biallelic inactivation in the second tumor suggested chemoresistance to cisplatin. This was further confirmed by tumor progression during second-line treatment. In case 3, the molecular analysis revealed different profiles in the three tumors, thus suggesting distinct tumor cell origins. CONCLUSION: These rare cases should alert clinicians of the possibility of multiple GCTs that should not be considered to be relapses. The underlying physiopathology is unknown, but multiple PGC mismigrations is a likely cause. Initial treatment with cisplatin may select chemo-resistant clones, thereby making the subsequent treatment more of a challenge.

Population and evolutionary genetics of the PAH locus to uncover overdominance and adaptive mechanisms in phenylketonuria: Results from a multiethnic study.

BACKGROUND: Phenylketonuria (PKU) is the most common inborn error of amino acid metabolism in Europe. The reasons underlying the high prevalence of heterozygous carriers are not clearly understood. We aimed to look for pathogenic PAH variant enrichment according to geographical areas and patients' ethnicity using a multiethnic nationwide cohort of patients with PKU in France. We subsequently appraised the population differentiation, balancing selection and the molecular evolutionary history of the PAH locus. METHODS: The French nationwide PKU study included patients who have been referred at the national level to the University Hospital of Nancy, and for whom a molecular diagnosis of phenylketonuria was made by Sanger sequencing. We performed enrichment analyses by comparing alternative allele frequencies using Fisher's exact test with Bonferroni adjustment. We estimated the amount of genetic differentiation among populations using Wright's fixation index (Fst). To estimate the molecular evolutionary history of the PAH gene, we performed phylogenetic and evolutionary analyses using whole-genome and exome-sequencing data from healthy individuals and non-PKU patients, respectively. Finally, we used exome-wide association study to decipher potential genetic loci associated with population divergence on PAH. FINDINGS: The study included 696 patients and revealed 132 pathogenic PAH variants. Three geographical areas showed significant enrichment for a pathogenic PAH variant: North of France (p.Arg243Leu), North-West of France (p.Leu348Val), and Mediterranean coast (p.Ala403Val). One PAH variant (p.Glu280Gln) was significantly enriched among North-Africans (OR = 23·23; 95% CI: 9·75-55·38). PAH variants exhibiting a strong genetic differentiation were significantly enriched in the 'Biopterin_H' domain (OR = 6·45; 95% CI: 1·99-20·84), suggesting a balancing selection pressure on the biopterin function of PAH. Phylogenetic and timetree analyses were consistent with population differentiation events on European-, African-, and Asian-ancestry populations. The five PAH variants most strongly associated with a high selection pressure were phylogenetically close and were located within the biopterin domain coding region of PAH or in its vicinity. Among the non-PAH loci potentially associated with population divergence, two reached exome-wide significance: SSPO (SCO-spondin) and DBH (dopamine beta-hydroxylase), involved in neuroprotection and metabolic adaptation, respectively. INTERPRETATION: Our data provide evidence on the combination of evolutionary and adaptive events in populations with distinct ancestries, which may explain the overdominance of some genetic variants on PAH. FUNDING: French National Institute of Health and Medical Research (INSERM) UMR_S 1256.

Evaluation of Outcomes and Quality of Care in Children with Sickle Cell Disease Diagnosed by Newborn Screening: A Real-World Nation-Wide Study in France.

This study's objective was to assess, on a national scale, residual risks of death, major disease-related events, and quality of care during the first five years in children diagnosed at birth with sickle cell disease (SCD). Data were retrospectively collected from medical files of all children with SCD born between 2006-2010 in France. Out of 1792 eligible subjects, 1620 patients (71.8% SS or S/beta°-thalassemia -SB°-) had available follow-up data, across 69 centers. Overall probability of survival by five years was 98.9%, with 12/18 deaths related to SCD. Probability of overt stroke by five years in SS/SB° patients was 1.1%, while transcranial Doppler (TCD) was performed in 81% before three years of age. A total of 26 patients had meningitis/septicemia (pneumococcal in eight cases). Prophylactic penicillin was started at a median age of 2.2 months and 87% of children had received appropriate conjugate pneumococcal vaccination at one year. By five years, the probability of survival without SCD-related events was 10.7% for SS/SB° patients. In contrast, hydroxyurea was prescribed in 13.7% and bone marrow transplant performed in nine patients only. In this study, residual risks of severe complications were low, probably resulting from a good national TCD, vaccination, and healthcare system coverage. Nonetheless, burden of disease remained high, stressing the need for disease-modifying or curative therapy.

Late effects after hematopoietic stem cell transplantation for ß-thalassemia major: the French national experience.

In this retrospective study, we evaluate long-term complications in nearly all ß-thalassemia-major patients who successfully received allogeneic hematopoietic stem cell transplantation in France. Ninety-nine patients were analyzed with a median age of 5.9 years at transplantation. The median duration of clinical follow up was 12 years. All conditioning regimens were myeloablative, most were based on busulfan combined with cyclophosphamide, and more than 90% of patients underwent a transplant from a matched sibling donor. After transplantation, 11% of patients developed thyroid dysfunction, 5% diabetes, and 2% heart failure. Hypogonadism was present in 56% of females and 14% of males. Female patients who went on to normal puberty after transplant were significantly younger at transplantation than those who experienced delayed puberty (median age 2.5 vs 8.7 years). Fertility was preserved in 9 of 27 females aged 20 years or older and 2 other patients became pregnant following oocyte donation. In addition to patient's age and higher serum ferritin levels at transplantation, time elapsed since transplant was significantly associated with decreased height growth in multivariate analysis. Weight growth increased after transplantation particularly in females, 36% of adults being overweight at last evaluation. A comprehensive long-term monitoring, especially of endocrine late effects, is required after hematopoietic stem cell transplantation for thalassemia.

[Preventative and therapeutic relapse strategies after allogeneic hematopoietic stem cell transplantation: Guidelines from the Francophone society of bone marrow transplantation and cellular therapy (SFGM-TC)]. / Stratégies préventives et thérapeutiques de la rechute après allogreffe de cellules souches hématopoïétiques : recommandations de la Société francophone de greffe de moelle et de thérapie cellulaire (SFGM-TC).

Disease relapse remains the first cause of mortality of hematological malignancies after allogeneic hematopoietic stem cell transplantation (allo-HCT). The risk of recurrence is elevated in patients with high-risk cytogenetic or molecular abnormalities, as well as when allo-HCT is performed in patients with refractory disease or with persistent molecular or radiological (PET-CT scan) residual disease. Within the frame of the 7th annual workshops of the francophone society for bone marrow transplantation and cellular therapy, the working group reviewed the literature in order to elaborate unified guidelines for the prevention and treatment of relapse after allo-HCT. For high risk AML and MDS, a post transplant maintenance strategy is possible, using hypomethylating agents or TKI anti-FLT3 when the target is present. For Philadelphia positive ALL, there was a consensus for the use of post-transplant TKI maintenance. For lymphomas, there are no strong data on the use of post-transplant maintenance, and hence a preemptive strategy is recommended based on modulation of immunosuppression, close follow-up of donor chimerism, and donor lymphocytes infusion. For multiple myeloma, even though the indication of allo-HCT is controversial, our recommendation is post transplant maintenance using bortezomib, due to its a good toxicity profile without increasing the risk of GVHD.

Two Tumors in 1: What Should be the Therapeutic Target? Pediatric Germ Cell Tumor With Somatic Malignant Transformation.

BACKGROUND: Germ cell tumors with somatic malignant transformation (GCT with SMT) are rare in children and poorly described. Data are missing to determine if therapies should target the GCT, the SMT compound, or both simultaneously. PATIENTS AND METHODS: A retrospective national study was conducted in the Société Française des cancers de l'Enfant (SFCE) Centers. Medical records from patients aged 0 to 18 years diagnosed with GCT with SMT between 2000 and 2015 were analyzed. Any stages and primary sites were considered as well as synchronous and metachronous cases. RESULTS: Fifteen patients were identified. Thirteen patients had synchronous GCT with SMT. In the latter cases, primaries were ovary (5), mediastinum (3), pineal gland (3), sacrococcyx (1), and parametrium (1). SMT histologies were central primitive neuroectodermal tumor (5), embryonal rhabdomyosarcomas (3) or thyroid papillary adenocarcinoma, leukemia, poorly differentiated carcinoma, mixed sarcomas, and miscellaneous histology (1 case each). Chemotherapy was targeted against the GCT (3), the SMT (6), or both components (3). The last patient received surgery exclusively. Partial or complete response to chemotherapy was observed in 5/10 assessable cases: 2/3 patients treated with GCT-dedicated chemotherapy, 3/6 patients treated with SMT-dedicated therapy, and 0/1 treated with combined therapy. In addition, 2 patients with mediastinal GCT primary had metachronous SMT, with acute myeloid leukemia and thyroid papillary adenocarcinoma, 8 months and 8 years, respectively, after the diagnoses of GCT. Two patients (1 synchronous and 1 metachronous) were cured with surgery exclusively. At the end of follow-up, 6 patients died of their disease including all 4 with postsurgical macroscopic residue. CONCLUSIONS: GCT with SMT constitutes a very rare entity in children and adolescents. Surgical removal of the tumor is the cornerstone of the treatment and might be sufficient in selected cases. In the remaining cases, the best management is still unknown and should take into account both components and their respective chemosensitivity. Long-term surveillance is advised for patient with unresected teratoma as late transformation can occur.

Cardiac iron overload in chronically transfused patients with thalassemia, sickle cell anemia, or myelodysplastic syndrome.

The risk and clinical significance of cardiac iron overload due to chronic transfusion varies with the underlying disease. Cardiac iron overload shortens the life expectancy of patients with thalassemia, whereas its effect is unclear in those with myelodysplastic syndromes (MDS). In patients with sickle cell anemia (SCA), iron does not seem to deposit quickly in the heart. Our primary objective was to assess through a multicentric study the prevalence of cardiac iron overload, defined as a cardiovascular magnetic resonance T2*<20 ms, in patients with thalassemia, SCA, or MDS. Patient inclusion criteria were an accurate record of erythrocyte concentrates (ECs) received, a transfusion history >8 ECs in the past year, and age older than 6 years. We included from 9 centers 20 patients with thalassemia, 41 with SCA, and 25 with MDS in 2012-2014. Erythrocytapharesis did not consistently prevent iron overload in patients with SCA. Cardiac iron overload was found in 3 (15%) patients with thalassemia, none with SCA, and 4 (16%) with MDS. The liver iron content (LIC) ranged from 10.4 to 15.2 mg/g dry weight, with no significant differences across groups (P = 0.29). Abnormal T2* was not significantly associated with any of the measures of transfusion or chelation. Ferritin levels showed a strong association with LIC. Non-transferrin-bound iron was high in the thalassemia and MDS groups but low in the SCA group (P<0.001). Hepcidin was low in thalassemia, normal in SCA, and markedly elevated in MDS (P<0.001). Two mechanisms may explain that iron deposition largely spares the heart in SCA: the high level of erythropoiesis recycles the iron and the chronic inflammation retains iron within the macrophages. Thalassemia, in contrast, is characterized by inefficient erythropoiesis, unable to handle free iron. Iron accumulation varies widely in MDS syndromes due to the competing influences of abnormal erythropoiesis, excess iron supply, and inflammation.

[Transfer of allogeneic stem cell transplant recipients to the intensive care unit: Guidelines from the Francophone society of marrow transplantation and cellular therapy (SFGM-TC)]. / Transfert des patients allogreffés de cellules-souches hématopoïétiques en réanimation : recommandations de la Société francophone de greffe de moelle et de thérapie cellulaire (SFGM-TC).

Transferring a patient undergoing an allogeneic stem cell transplantation to the intensive care unit (ICU) is always a challenging situation on a medical and psychological point of view for the patient and his relatives as well as for the medical staff. Despite the progress in hematology and intensive care during the last decade, the prognosis of these patients admitted to the ICU remains poor and mortality is around 50 %. The harmonization working party of the SFGM-TC assembled hematologists and intensive care specialist in order to improve conditions and modalities of the transfer of a patient after allogeneic stem cell transplantation to the ICU. We propose a structured medical form comprising all essential information necessary for optimal medical care on ICU.

A New Intergenic α-Globin Deletion (α-αΔ125) Found in a Kabyle Population.

We have identified a deletion of 125 bp (α-α(Δ125)) (NG_000006.1: g.37040_37164del) in the α-globin gene cluster in a Kabyle population. A combination of singlex and multiplex polymerase chain reaction (PCR)-based assays have been used to identify the molecular defect. Sequencing of the abnormal PCR amplification product revealed a novel α1-globin promoter deletion. The endpoints of the deletion were characterized by sequencing the deletion junctions of the mutated allele. The observed deletion was located 378 bp upstream of the α1-globin gene transcription initiation site and leaves the α2 gene intact. In some patients, the α-α(Δ125) deletion was shown to segregate with Hb S (HBB: c.20A>T) and/or Hb C (HBB: c.19G>A) or a ß-thalassemic allele. The α-α(Δ125) deletion has no discernible effect on red cell indices when inherited with no other abnormal globin genes. The family study demonstrated that the deletion is heritable. This is the only example of an intergenic α2-α1 non coding DNA deletion, leaving the α2-globin gene and the α1 coding part intact.

Genotype-phenotype associations in French patients with phenylketonuria and importance of genotype for full assessment of tetrahydrobiopterin responsiveness.

BACKGROUND: Mutations in Phenylalanine Hydroxylase (PAH) gene cause phenylketonuria. Sapropterin (BH4), the enzyme cofactor, is an important therapeutical strategy in phenylketonuria. However, PAH is a highly polymorphic gene and it is difficult to identify BH4-responsive genotypes. We seek here to improve prediction of BH4-responsiveness through comparison of genotypes, BH4-loading test, predictions of responsiveness according to the literature and types and locations of mutations. METHODS: A total of 364 French patients among which, 9 % had mild hyperphenylalaninemia, 17.7 % mild phenylketonuria and 73.1 % classical phenylketonuria, benefited from a 24-hour BH4-loading test and had the PAH gene sequenced and analyzed by Multiplex Ligation Probe Amplification. RESULTS: Overall, 31.6 % of patients were BH4-responsive. The number of different mutations found was 127, including 26 new mutations. The mutations c.434A > T, c.500A > T, c.529G > C, c.1045 T > G and c.1196 T > C were newly classified as being BH4-responsive. We identified 261 genotypes, among which 46 were newly recognized as being BH4-responsive. Even though patients carry 2 responsive alleles, BH4-responsiveness cannot be predicted with certainty unless they present mild hyperphenylalaninemia. BH4-responsiveness cannot be predicted in patients carrying one responsive mutation only. In general, the milder the phenotype is, the stronger the BH4-response is. Almost exclusively missense mutations, particularly in exons 12, 11 and 8, are associated with BH4-responsiveness and any other type of mutation predicts a negative response. CONCLUSIONS: This study is the first of its kind, in a French population, to identify the phenotype associated with several combinations of PAH mutations. As others, it highlights the necessity of performing simultaneously BH4 loading test and molecular analysis in monitoring phenylketonuria patients.