Approche thérapeutique des maladies de Castleman : l'émergence des thérapies ciblées.

The spectrum of Castleman disease encompasses several different disorders. Nowadays three different forms of the disease are individualized: unicentric Castleman disease, multicentric HHV-8 associated Castleman disease and idiopathic multicentric Castleman disease. In the latter a severe form called TAFRO syndrome (thrombocytopenia, anasarca, myelofibrosis, renal dysfunction, and organomegaly) tend to be individualized. Improvement in the classification and understanding of the physiopathology of CD have allowed improvement in treatment strategies. Treatment of rare but often severe manifestations, such as paraneoplastic pemphigus and bronchiolitis obliterans in unicentric CD and hemophagocytic syndrome and/or Kaposi' sarcoma in HHV8 associated CD, are better adapted. Most of current treatment strategies are based on retrospective and very few prospective studies. Both anti-IL6/6R and anti-CD20 biotherapies have greatly improved the management of certain forms of the disease. We report in this review the most relevant studies and national or international expert consensus statements for the treatment in the different types of CD. © 2022 Published by Elsevier Masson SAS on behalf of Société nationale française de médecine interne (SNFMI).

Prognosis of Lymphoma in Patients With Known Inflammatory Bowel Disease: A French Multicentre Cohort Study.

BACKGROUND AND AIMS: The prognosis of lymphoma that occurs in patients with inflammatory bowel disease [IBD] is poorly known. METHODS: A multicentre retrospective cohort analysis was done in seven French tertiary centres from 1999 to 2019. Only lymphoma occurring in patients with previous established diagnosis of IBD were analysed. The primary outcome was progression-free survival at 3 years. RESULTS: A total of 52 patients [male 65%, Crohn's disease 79%, median age 48.3 years, median duration of IBD 10.1 years] were included, of whom 37 had been previously exposed to immunosuppressants and/or biologics for at least 3 months and 20 had primary intestinal lymphomas. The lymphoma histological types were: diffuse large B cell lymphomas [N = 17], Hodgkin lymphomas [N = 17], indolent B cell lymphomas [N = 12], and others including T cell lymphomas, mantle cell lymphomas, and unclassifiable B cell lymphoma [N = 6]. The median follow-up after lymphoma was 5.1 years (interquartile range [IQR] 4-7.8). Progression-free survival at 3 years was 85% in the overall population (95% confidence interval [CI] 75%-96%) with no significant difference between the exposed and unexposed group, 79% for patients exposed to immunosuppressants and/or biologics [95% CI 67%-94%], and 83% for patients diagnosed with primary intestinal lymphoma [95% CI 67%-100%]. No relapse of IBD has been observed during chemotherapy. The IBD relapse rate at the end of the last chemotherapy cycle was 23% at 3 years [95% CI 11%-39%] in the overall population. CONCLUSIONS: In this large cohort, the prognosis for lymphomas occurring in IBD appears to be good and similar to what is expected, irrespective of the exposure to biologics and/or immunosuppressants.

Factors associated with tuberculosis-associated haemophagocytic syndrome: a multicentre case-control study.

SETTING: Tuberculosis (TB) is a potential trigger of haemophagocytic syndrome (HS) but little is known about the features of TB-associated HS.OBJECTIVE: To assess the risk factors associated with HS in patients with TB.DESIGN: We performed a multicentre case-control study assessing the medical records of adult patients diagnosed with proven TB with (TB/HS+) or without (TB/HS-) associated HS.RESULTS: Twenty-one patients with TB/HS+ (24% women, median age, 37 years [IQR 30-48]) were included in the study. Eleven patients (52%) were infected with human immunodeficiency virus and seven patients (33%) were immunocompromised due to other reasons. TB was disseminated in 17 patients (81%). Compared with 50 control TB patients (TB/HS-), patients with TB/HS+ were more likely to be immunocompromised (86% vs. 18%; P < 0.001) and to present with disseminated TB (80% vs. 12%; P < 0.001). The outcome was poorer in patients with TB/HS+, with a higher admission rate to intensive care (71% vs. 0%; P < 0.001) and a higher risk of death (38% vs. 7%; P = 0.005).CONCLUSION: TB/HS+ occurred more likely in immunocompromised patients and severely impaired the prognosis of TB. Further studies are needed to devise therapeutic strategies for patients with TB/HS+.

Prognosis of autoimmune hemolytic anemia in critically ill patients.

Patients with autoimmune hemolytic anemia (AIHA) may require intensive care unit (ICU) admission. In order to describe the characteristics of AIHA patients in ICU and identify prognosis factors, clinical and biological data from 44 patients admitted in one ICU between 2002 and 2015 were retrospectively analyzed. The main reasons for ICU admission were profound anemia without any organ failure in 19 patients (either for safer transfusion or continuous monitoring only). Twenty-five (57%) patients had a past history of hemopathy. Twenty patients presented with a direct anti-globulin test (DAT) positive for immunoglobulin G (DAT-IgG) only (46%), 8 with a DAT positive for both IgG and complement (DAT-IgG+C) (36%), and 16 with a DAT positive for complement only (DAT-IgG+C) (18%). Corticosteroids and rituximab were administered to respectively 44 (100%) and 12 (25%) patients. Red blood cell transfusion was required in 28 (64%) patients. Ten (23%) patients received vasopressors. Renal replacement therapy was necessary in 14 (31.8%) patients. Thirteen (30%) patients died in the ICU. There was no difference between survivors and non-survivors regarding associated comorbidities like hemopathy (18/31 [58%] vs. 7/13 [54%], p = 0.80). In decedents, age was higher (72 years [57.8-76.3] vs. 50 years [34.3-64], p < 0.01) and organ dysfunctions were more severe at day 1 (SOFA 8 [7-11] vs. 5.5 [3-7], p < 0.01). Patients with a DAT-IgG displayed poorer outcome in comparison with patients with DAT-IgG+C/C (hospital mortality 69% vs. 36%, p = 0.04). Mortality rate of AIHA patients requiring ICU admission is consequential and appears to be impacted by age, organ failures, and DAT-IgG.

Quality of life in systemic lupus erythematosus: description in a cohort of French patients and association with blood hydroxychloroquine levels.

OBJECTIVES: Benefits of hydroxychloroquine (HCQ) use on physician reported outcomes are well documented in systemic lupus erythematosus (SLE). We assess for the first time the association and predictive value of blood HCQ levels towards health-related quality of life (HRQOL) in SLE. METHODS: Data from the PLUS study (a randomized, double-blind, placebo-controlled, multicentre study) were utilized. Blood HCQ levels were quantified by high-performance liquid chromatography along with HRQOL assessments (Medical Outcomes Study-SF-36) at baseline (V1) and month 7 (V2). RESULTS: 166 SLE patients' data were analysed. Mean (SD) age and disease duration were 44.4 (10.7) and 9.3 (6.8) years. Eighty-seven per cent were women. Mean (SD, median, IQR) HCQ concentrations in the blood at V1 were 660 (314, 615, 424) ng/ml and increased to 1020 (632, 906, 781) ng/ml at V2 (mean difference 366 units, 95% confidence interval -472 to -260, p < 0.001). No significant correlations between HCQ concentrations with HRQOL domains at V1 or V2 were noted. There were no differences in HRQOL stratified by HCQ concentrations. HCQ concentrations at V1 or changes in HCQ concentration (V2-V1) were not predictive of HRQOL at V2 or changes in HRQOL (V2-V1). CONCLUSIONS: No association of HCQ concentrations with current or longitudinal HRQOL were found in SLE.

[Pseudo-adult Still's disease, anasarca, thrombotic thrombocytopenic purpura and dysautonomia: An atypical presentation of multicentric Castleman's disease. Discussion of TAFRO syndrome]. / Pseudo-maladie de Still, anasarque, microangiopathie thrombotique et dysautonomie : présentation atypique d'une maladie de Castleman multicentrique. Discussion du syndrome TAFRO.

INTRODUCTION: Multicentric Castleman's disease can mimic adult-onset Still disease. It is exceptionally associated with anasarca, thrombotic microangiopathy and dysautonomia. CASE REPORT: We report a 32-year-old woman with an association of oligoanuria, anasarca, thrombotic microangiopathy with features compatible with adult-onset Still disease. The outcome was initially favorable with corticosteroids, immunoglobulins and plasmapheresis but with the persistence of relapses marked by severe autonomic syndrome and necessity of high dose corticosteroids. The diagnosis of mixed type Castleman's disease, HHV8 and HIV negative, was obtained four years after the onset of symptoms by a lymph node biopsy. The outcome was favorable after tocilizumab and corticosteroids but tocilizumab had to be switched to anakinra to ensure a proper and long-lasting control of the disease. CONCLUSION: Our patient partially fits the description of TAFRO syndrome (Thrombocytopenia, Anasarca, myeloFibrosis, Renal dysfunction, Organomegaly), a MCM rare variant, recently described in Japanese patients.

Diversity and combinations of infectious agents in 38 adults with an infection-triggered reactive haemophagocytic syndrome: a multicenter study.

Reactive haemophagocytic syndrome (HS) is a rare condition that occurs in patients with infections, haematological malignancies or autoimmune diseases. Although various microorganisms are thought to trigger HS, most of the literature data on this topic have been gathered in single-centre case series. Here, we sought to characterize infectious triggers in a large, multicentre cohort of patients with HS. Patients were included in the present study if HS was solely due to one or more infections. Detailed microbiological data were recorded. Of the 162 patients with HS in the cohort, 40 (25%) had at least one infection and 38 of the latter (including 14 women, 36.8%) were included. The median age was 46 years. Seven patients were presumed to be immunocompetent (18.4%), whereas 19 patients (50%) were infected with human immunodeficiency virus and 12 patients (31.6%) were immunocompromised for other reasons. Twenty-seven patients (71.1%) had a single infection, whereas six (15.8%) and five (13.1%) patients had, respectively, two and three concomitant infections. We observed pyogenic bacterial infections (n = 7), tuberculosis (n = 10), non-tuberculous mycobacteriosis (n = 3), viral infections (n = 17: 11 cytomegalovirus, three Epstein-Barr virus, two human herpesvirus 8, one herpes simplex virus 2), parasitic infections (n = 8: four disseminated toxoplasmosis, one leishmaniasis, three malaria), fungal infections (n = 5: four pulmonary pneumocystosis and one candidaemia). Eighteen patients (47.4%) received corticosteroids and/or etoposide. Twelve patients died (31.6%). All multiple infections and all deaths occurred in immunocompromised patients. When compared with patients suffering from malignancy-associated HS, patients with infection-triggered HS were younger and more likely to be immunocompromised, and had a better outcome.

Determinants of hydroxychloroquine blood concentration variations in systemic lupus erythematosus.

OBJECTIVE: Blood concentrations of hydroxychloroquine (HCQ) vary widely among patients with systemic lupus erythematosus (SLE). A pharmacokinetic/pharmacodynamic relationship has been found in different situations, and a very low blood concentration of HCQ is a simple marker of nonadherence to treatment. Therefore, interest in blood HCQ concentration measurement has increased, but little is known about factors that influence blood HCQ concentration variability. This study was undertaken to analyze determinants of blood HCQ concentrations. METHODS: We conducted a retrospective analysis of patient data, including data from the Plaquenil Lupus Systemic (PLUS) study, to determine the association of epidemiologic, clinical, and biologic factors with blood HCQ concentrations. Data for nonadherent patients (blood HCQ concentration <200 ng/ml) were excluded. RESULTS: To examine homogeneous pharmacologic data, we restricted the analyses of the PLUS data to the 509 SLE patients receiving 400 mg/day. We found no association of ethnicity or smoking with blood HCQ concentrations and no pharmacokinetic drug-drug interaction with antacids or with inhibitors or inducers of cytochrome P450 enzymes. On multivariate analysis, high body mass index (P = 0.008), no treatment with corticosteroids (P = 0.04), increased time between the last tablet intake and measurement of blood HCQ concentrations (P = 0.017), low platelet count (P < 0.001), low neutrophil count (P < 0.001), and high estimated creatinine clearance (P < 0.001) were associated with low blood HCQ concentrations. In 22 SLE patients with chronic renal insufficiency (median serum creatinine clearance 52 ml/minute [range 23-58 ml/minute]) who received 400 mg/day HCQ, the median blood HCQ concentration was significantly higher than that in the 509 patients from the PLUS study (1,338 ng/ml [range 504-2,229 ng/ml] versus 917 ng/ml [range 208-3316 ng/ml]) (P < 0.001). CONCLUSION: We provide a comprehensive analysis of determinants of blood HCQ concentrations. Because this measurement is increasingly being used, these data might be useful for clinicians.

Changes in the influence of lymphoma- and HIV-specific factors on outcomes in AIDS-related non-Hodgkin lymphoma.

BACKGROUND: We undertook the present analysis to examine the shifting influence of prognostic factors in HIV-positive patients diagnosed with aggressive non-Hodgkin lymphoma (NHL) over the last two decades. PATIENTS AND METHODS: We carried out a pooled analysis from an existing database of patients with AIDS-related lymphoma. Individual patient data had been obtained prior from prospective phase II or III clinical trials carried out between 1990 until 2010 in North America and Europe that studied chemo(immuno)therapy in HIV-positive patients diagnosed with AIDS-related lymphomas. Studies had been identified by a systematic review. We analyzed patient-level data for 1546 patients with AIDS-related lymphomas using logistic regression and Cox proportional hazard models to identify the association of patient-, lymphoma-, and HIV-specific variables with the outcomes complete response (CR), progression-free survival, and overall survival (OS) in different eras: pre-cART (1989-1995), early cART (1996-2000), recent cART (2001-2004), and contemporary cART era (2005-2010). RESULTS: Outcomes for patients with AIDS-related diffuse large B-cell lymphoma and Burkitt lymphoma improved significantly over time, irrespective of baseline CD4 count or age-adjusted International Prognostic Index (IPI) risk category. Two-year OS was best in the contemporary era: 67% and 75% compared with 24% and 37% in the pre-cART era (P < 0.001). While the age-adjusted IPI was a significant predictor of outcome in all time periods, the influence of other factors waxed and waned. Individual HIV-related factors such as low CD4 counts (<50/mm(3)) and prior history of AIDS were no longer associated with poor outcomes in the contemporary era. CONCLUSIONS: Our results demonstrate a significant improvement of CR rate and survival for all patients with AIDS-related lymphomas. Effective HIV-directed therapies reduce the impact of HIV-related prognostic factors on outcomes and allow curative antilymphoma therapy for the majority of patients with aggressive NHL.

Cardiac troponin-I on diagnosis predicts early death and refractoriness in acquired thrombotic thrombocytopenic purpura. Experience of the French Thrombotic Microangiopathies Reference Center.

BACKGROUND: Cardiac involvement is a major cause of mortality in patients with thrombotic thrombocytopenic purpura (TTP). However, diagnosis remains underestimated and delayed, owing to subclinical injuries. Cardiac troponin-I measurement (cTnI) on admission could improve the early diagnosis of cardiac involvement and have prognostic value. OBJECTIVES: To assess the predictive value of cTnI in patients with TTP for death or refractoriness. PATIENTS/METHODS: The study involved a prospective cohort of adult TTP patients with acquired severe ADAMTS-13 deficiency (< 10%) and included in the registry of the French Reference Center for Thrombotic Microangiopathies. Centralized cTnI measurements were performed on frozen serum on admission. RESULTS: Between January 2003 and December 2011, 133 patients with TTP (mean age, 48 ± 17 years) had available cTnI measurements on admission. Thirty-two patients (24%) had clinical and/or electrocardiogram features. Nineteen (14.3%) had cardiac symptoms, mainly congestive heart failure and myocardial infarction. Electrocardiogram changes, mainly repolarization disorders, were present in 13 cases. An increased cTnI level (> 0.1 µg L(-1) ) was present in 78 patients (59%), of whom 46 (59%) had no clinical cardiac involvement. The main outcomes were death (25%) and refractoriness (17%). Age (P = 0.02) and cTnI level (P = 0.002) showed the greatest impact on survival. A cTnI level of > 0.25 µg L(-1) was the only independent factor in predicting death (odds ratio [OR] 2.87; 95% confidence interval [CI] 1.13-7.22; P = 0.024) and/or refractoriness (OR 3.03; 95% CI 1.27-7.3; P = 0.01). CONCLUSIONS: A CTnI level of > 0.25 µg L(-1) at presentation in patients with TTP appears to be an independent factor associated with a three-fold increase in the risk of death or refractoriness. Therefore, cTnI level should be considered as a prognostic indicator in patients diagnosed with TTP.

Acute renal failure is prevalent in patients with thrombotic thrombocytopenic purpura associated with low plasma ADAMTS13 activity.

BACKGROUND: Among patients with thrombotic microangiopathies, acute kidney injury (AKI) is the hallmark of hemolytic uremic syndrome (HUS) and is largely underestimated in patients with thrombotic thrombocytopenic purpura (TTP). OBJECTIVE: We sought to report AKI features and outcomes in patients with TTP. METHODS: We conducted a retrospective study of 92 patients with TTP assessed by low ADAMTS13 activity (< 10%) between 2001 and 2013. A logistic regression identified variables independently associated with AKI. RESULTS: Among the 92 patients, 54 (58.7%) presented with AKI, including 25 (46.3%) with stage 3 AKI. Fourteen (27.4%) patients had a nephrotic-range proteinuria and 21 (45.6%) had hemoglobinuria. Hematuria and leucocyturia were detected in 19 (41.3%) and 16 patients (36.4%), respectively. Renal replacement therapy (RRT) was required in 14 patients (25.9%). Six months after TTP remission, RRT-free patients had median (IQR) MDRD (Modification of Diet in Renal Disease formula estimating the glomerular filtration rate) of 93 mL min(-1) per 1.73 m(2) (68.8-110) and three patients required long-term dialysis. Mild or moderate chronic renal disease occurred in 23/54 (42.6%) AKI patients. By multivariate analysis, serum level of complement component 3 at admission was the only factor independently associated with AKI (OR per 0.25 unit decrease of C3, 0.85; CI, 1.82-8.33; P = 0.001). CONCLUSIONS: In patients with TTP, AKI is present in more than half the patients, and half of those will have lasting renal effects. Further studies to better understand the pathophysiology of renal involvement in patients with TTP and to identify a subset of patients with TTP syndrome overlapping HUS are warranted.

Optic neuritis revealing Kikuchi-Fujimoto disease.

Kikuchi-Fujimoto disease is a rare systemic disease with uncommon neurological involvement. We report the case of a 30-year-old Asian woman who presented a rapidly progressive loss of vision. Magnetic resonance imaging (MRI) of the optic nerve revealed an inflammation of the left optic nerve with chiasmatic involvement, without any encephalic or medullar lesion. Thoracic computed tomography scan showed bilateral axillary lymphadenopathy. Analysis of a biopsy of the axillary lymph node showed typical histological findings of Kikuchi-Fujimoto disease. There was no clinical or biological sign of associated systemic lupus erythematosus. The patient spontaneously recovered normal visual acuity in 4 weeks, with resolution of MRI abnormalities. No optic neuritis relapse or neurological event occurred in a 3-year follow-up. To our knowledge this is the first case of optic neuritis associated with Kikuchi-Fujimoto disease.

[Hemophagocytic lymphohistiocytosis]. / Le syndrome d'activation lymphohistiocytaire de l'adulte.

Hemophagocytic lymphohistiocytosis is a life-threatening condition associated with multiple organ dysfunctions. This entity is related to inappropriate stimulation and proliferation of cytotoxic lymphocytes and macrophages inducing phagocytosis of blood cells. Hemophagocytic lymphohistiocytosis should be considered rapidly in any unexplained febrile cytopenia. Biological markers are high ferritin and triglyceride levels, and low fibrinogen. Hemophagocytic lymphohistiocytosis diagnosis should not be ruled on or out solely on the presence or absence of hemophagocytosis features on smear or biopsy sampling. It is either "primary/genetic" (pediatric or familial disorders) and characterized by a lack of intrinsic cytotoxicity of NK cells or T CD8 lymphocyte, or "secondary/reactive" due to malignancy, infectious or autoimmune origin. Mortality is 50% (including all etiologies), and this severity requires rapid and "aggressive" investigations with multidisciplinary approach including intensive care unit team. The immediate aim of therapy is suppression of the severe hyper-inflammation, which can lead to multiple organ failure. Emergency treatment is currently based on etoposide (VP16), pending to the identification and treatment of underlying cause.

Human herpesvirus 8-related Castleman disease in the absence of HIV infection.

BACKGROUND: Castleman disease (CD) in the context of human immunodeficiency virus (HIV) infection is well described. It is almost always multicentric (MCD) and linked to human herpesvirus 8 (HHV-8). There are limited published data surrounding HHV-8-related CD among HIV-negative patients. METHODS: From January 1995 through June 2012, we identified in a single center 18 HIV-seronegative patients with HHV-8-related CD. We report on their clinical, pathological, and laboratory features. RESULTS: All cases were multicentric. Patients were aged 42-83 years and were referred with a relapsing remitting syndrome of fever (94%), constitutional symptoms (100%), peripheral lymphadenopathy (100%), splenomegaly (72%), hepatomegaly (50%), and edema (28%). Kaposi sarcoma was observed in 9 cases. Anemia and serum markers of inflammation were present in all cases. Polymerase chain reaction for HHV-8 DNA was positive on blood samples in all cases, whereas only 12 of 16 patients tested had positive HHV-8 serology at diagnosis. All cases showed the classic histological features of MCD, and LANA-1 immunostaining identified HHV-8-infected plasmablasts in 16 of 16 tested cases. Reactive hemophagocytic syndrome (44%), autoimmune hemolytic anemia (33%), and lymphoma (22%) were the commonest associated complications. Remission was obtained with etoposide in 13 of 15 cases. Rituximab allowed prolonged remission off therapy in 10 cases. Death occurred in 3 patients not treated with rituximab. These features were similar to those described in HIV-positive HHV-8-related MCD. Comparison between these 18 cases and 12 HIV-negative HHV-8-unrelated MCD cases showed marked discrepancies. CONCLUSIONS: HHV-8-associated MCD may be considered as a single clinicopathological entity regardless of HIV status.

[Pulmonary involvement due to HHV-8 virus during the course of HIV infection]. / Atteintes pulmonaires liées au virus HHV-8 au cours de l'infection VIH.

HHV-8 is a herpes virus discovered in 1994 in Kaposi sarcoma cells. Its involvement was later demonstrated in multicentric Castleman disease and in primary lymphoma effusion lymphoma. These diseases arise almost exclusively in immunocompromised patients, mostly in association with HIV infection. Apart from Kaposi's sarcoma, combined antiretroviral therapy does not seem to have reduced the incidence of these diseases, which remain rare. In these three diseases, pulmonary involvement is common and may be the presenting feature. Kaposi's sarcoma of the lung is usually asymptomatic but may require specific therapy. Pulmonary involvement is mostly associated with cutaneous disease. Patients with Castleman disease typically present with fever and lymphadenopathy, associated with interstitial lung disease without opportunistic infection. Patients with primary lymphoma effusion presents with fever and an exudative lymphocytic pleural effusion, without a pleural mass on the CT-scan. Rapid diagnosis of these conditions avoids unnecessary invasive examinations and leads to prompt specific treatment.

[Myeloproliferative hypereosinophilic syndrome revealed by bipolar mucosal ulcerations]. / Syndrome hyperéosinophilique d'origine myéloproliférative révélé par des ulcérations muqueuses bipolaires.

BACKGROUND: Hypereosinophilic syndrome (HES) is defined as an eosinophil count equal to or greater than 1.5 G/L for more than 6 months with organ damage (heart, nervous system, lung, etc) after the exclusion of other common causes of eosinophilia. A myeloproliferative variant of HES with FIP1L1-PDGFRα fusion gene inducing constitutive activation of a tyrosine kinase receptor has been characterized. We report a case in which the diagnosis was revealed by mucosal erosions and ulcerations. PATIENTS AND METHODS: A 50-year-old man reported bipolar erosions. He presented with an erosion on the glans, an ulceration on the lower lip and mild dermographism. He had an eosinophil count of 7.5 G/L (n<0.7) and raised LDH at 520 IU/L (n<480). Screening for the usual causes of eosinophilia was negative. Histology of the labial ulceration showed a polymorphous inflammatory infiltrate containing eosinophils. A chest scan demonstrated a ground glass-like pulmonary infiltrate and broncho-alveolar lavage revealed eosinophilic alveolitis. The myelogram showed rich bone marrow with eosinophils. FIP1L1-PDGFRα fusion transcript was detected in the blood. Imatinib (Glivec(®)) was initiated and a favourable outcome was achieved within a few months and maintained after one year of treatment. DISCUSSION: Cutaneous signs are frequent features of HES. They are polymorphous and include pruritis, erythematous rash and urticaria. Mucosal ulcerations are uncommon and appear more frequently with the myeloproliferative FIP1L1-PDGFRα-associated variant of HES. Early diagnosis allows the onset of a targeted treatment with imatinib that may prevent the apparition of organ damage.