Real-life effectiveness 1 year after switching to avalglucosidase alfa in late-onset Pompe disease patients worsening on alglucosidase alfa therapy: A French cohort study.

INTRODUCTION: Late-onset Pompe disease (LOPD) is characterized by a progressive myopathy resulting from a deficiency of acid α-glucosidase enzyme activity. Enzyme replacement therapy has been shown to be effective, but long-term treatment results vary. Avalglucosidase alfa demonstrated non-inferiority to alglucosidase alfa in a phase 3 study, allowing in France compassionate access for advanced LOPD patients unresponsive to alglucosidase alfa. METHODS: Data from the French Pompe registry were analyzed for patients who benefited from a switch to avalglucosidase alfa with at least 1 year of follow-up. Respiratory (forced vital capacity [FVC]) and motor functions (Six-Minute Walk Test [6MWT]) were assessed before and 1 year after switching. Individual changes in FVC and 6MWT were expressed as slopes and statistical analyses were performed to compare values. RESULTS: Twenty-nine patients were included (mean age 56 years, 11 years of prior treatment). The FVC and 6MWT values remained stable. The individual analyses showed a stabilization of motor worsening: -1 m/year on the 6MWT after the switch versus -63 m/year the year before the switch (i.e., a worsening of 33%/year before vs. an improvement of 3%/year later). Respiratory data were not statistically different. DISCUSSION: At the group level, gait parameters improved slightly with a stabilization of previous worsening, but respiratory parameters showed limited changes. At the individual level, results were discordant, with some patients with a good motor or respiratory response and some with further worsening. CONCLUSION: Switching to avalglucosidase alfa demonstrated varied responses in advanced LOPD patients with failing alglucosidase alfa therapy, with a general improvement in motor stabilization.

Successful treatment of JAK1-associated inflammatory disease.

BACKGROUND: Gain-of-function variants of JAK1 drive a rare immune dysregulation syndrome associated with atopic dermatitis, allergy, and eosinophilia. OBJECTIVES: This study sought to describe the clinical and immunological characteristics associated with a new gain-of-function variant of JAK1 and report the therapeutic efficacy of Janus kinase (JAK) inhibition. METHODS: The investigators identified a family affected by JAK1-associated autoinflammatory disease and performed clinical assessment and immunological monitoring on 9 patients. JAK1 signaling was studied by flow and mass cytometry in patients' cells at basal state or after immune stimulation. A molecular disease signature in the blood was studied at the transcriptomic level. Patients were treated with 1 of 2 JAK inhibitors: either baricitinib or upadacitinib. Clinical, cellular, and molecular response were evaluated over a 2-year period. RESULTS: Affected individuals displayed a syndromic disease with prominent allergy including atopic dermatitis, ichthyosis, arthralgia, chronic diarrhea, disseminated calcifying fibrous tumors, and elevated whole blood histamine levels. A variant of JAK1 localized in the pseudokinase domain was identified in all 9 affected, tested patients. Hyper-phosphorylation of STAT3 was found in 5 of 6 patients tested. Treatment of patients' cells with baricitinib controlled most of the atypical hyper-phosphorylation of STAT3. Administration of baricitinib to patients led to rapid improvement of the disease in all adults and was associated with reduction of systemic inflammation. CONCLUSIONS: Patients with this new JAK1 gain-of-function pathogenic variant displayed very high levels of blood histamine and showed a variable combination of atopy with articular and gastrointestinal manifestations as well as calcifying fibrous tumors. The disease, which appears to be linked to STAT3 hyperactivation, was well controlled under treatment by JAK inhibitors in adult patients.

Balance control impairments in Fabry disease.

Background: Fabry disease (FD) is a rare inherited lysosomal storage disorder caused by the deficiency of the enzyme alpha-galactosidase A. This deficiency leads to an accumulation of glycosphingolipids leading to progressive and multisystemic disease, including renal, cardiac, and neurological damages. FD may also have neuro-otological and visual impairments, which can generate postural control alterations, inner ear, and vision being involved in this function. This study aimed to evaluate the impact of FD on postural control. Methods: In total, fourteen adult patients (8 men/6 women, mean age = 37.6 ± 11.4 years) and two children (mean age = 11 years) with FD and 19 healthy adults (12 men/7 women, mean age = 36.5 ± 16.9 years) and two healthy children (mean age = 10.5 years) took part in this study. Postural control was evaluated by a sensory organization test combining three visual situations (eyes open, eyes closed, and sway referenced visual surround motion) with two platform situations (stable platform and sway referenced platform motion), aiming to calculate a composite equilibrium score (CES), a high score being representative of good postural control. Somatosensory (RSOM), visual (RVIS), and vestibular (RVEST) contributions to postural control were calculated, a low score reflecting a poor use of the indicated sensory input. Results: The CES was lower in adult patients with FD compared with the healthy subjects (p < 0.001). RVIS (p = 0.001) and RVEST (p = 0.003) were lower in patients with FD compared with the control group, whereas no difference in RSOM was observed. Conclusion: Inner ear and visual pathologies associated with the central nervous system impairments are factors of postural control impairments. Physical activities, which can also be rehabilitative, by maintaining or increasing the weight of proprioception, may help diminish dependency on altered sensorial inputs.

Effect of enzyme replacement therapy with alglucosidase alfa (Myozyme®) in 12 patients with advanced late-onset Pompe disease.

BACKGROUND: The efficacy of enzyme replacement therapy (ERT) in patients at an advanced stage of Pompe disease has only been addressed in a few studies. Our objective was to assess the long term effects of ERT in a cohort of patients with severe Pompe disease. METHODS: We identified patients from the French Pompe Registry with severe respiratory failure and permanent wheelchair use (assisted walk for a few meters was allowed) when starting ERT. Patients' medical records were collected and reviewed and respiratory and motor functions, before ERT initiation and upon last evaluation were compared. RESULTS: Twelve patients (7 males) were identified. Median age at symptom onset was 24years [IQR=15.5; 36.0]. At baseline ventilation was invasive in 11 patients and noninvasive in one, with a median ventilation time of 24h [IQR=21.88; 24.00] (min 20; max 24). ERT was initiated at a median age of 52.5years [IQR=35.75; 66.50]. Median treatment duration was 55months [IQR=39.5; 81.0]. During observational period no adverse reaction to ERT was recorded, five patients (41.67%) died, three decreased their ventilation time by 30, 60 and 90min and two increased their assisted walking distance, by 80 and 20m. CONCLUSION: Some patients at a very advanced stage of Pompe disease may show a mild benefit from ERT, in terms of increased time of autonomous ventilation and of enlarged distance in assisted walk. ERT can be initiated in these patients in order to retain their current level of independence and ability to perform daily life activities.

Systemic capillary leak syndrome and autoimmune diseases: A case series.

OBJECTIVES: Systemic capillary leak syndrome (Clarkson's disease) is a rare entity characterized by recurrent and unpredictable attacks of capillary leakage of plasma fluid and proteins throughout the endothelium. Some cases are secondary. We describe the rare association between secondary capillary leak syndrome (SCLS) and autoimmune diseases. METHODS: We conducted a nationwide, retrospective, observational, and collaborative study throughout the hospital units of the Club des Rhumatismes et Inflammations network (CRI) between March and August 2015. Inclusion criteria were patients with (1) capillary leakage episodes characterized by edema and elevated hematocrit, low albumin count without proteinuria, or other cause of protein loss; and (2) definite autoimmune diseases according to international classification criteria. RESULTS: The clinical and biological data of five patients (three women) were reviewed. Median age was 43.2 (17-55) years. Four patients had Sjögren syndrome. One of them also fulfilled the criteria for systemic sclerosis (n = 1). The fifth patient had polymyositis. During the 37.2 months of median follow-up (5.4-201), we recorded a total of 24 attacks, yielding an attack incidence of 91/100 patient-years. Laboratory tests revealed that three patients had anti-SSA/Ro antibodies. Only one patient had a monoclonal blood component (IgGκ). Three patients needed ICU support; one died during a flare. CONCLUSIONS: We reported the first case series of a rare association of SCLS and autoimmune diseases, supporting the idea of some immune mediation in the pathogenesis of the former disease.

Leukocyte differential for acute abdominal pain in adults.

BACKGROUND: Abdominal pain is a common symptom underlying a variety of disorders with different prognoses. Neutrophilia or lymphopenia have been used as prognostic markers in several stress- or infection-mediated disorders. We studied the clinical relevance of the leukocyte differential in the initial workup of adult patients presenting with abdominal pain. METHODS: We reviewed all leukocyte differentials and medical records of 441 consecutive patients admitted for abdominal pain in an emergency department. Patients were matched by age and sex with controls and were assigned to 4 groups: functional disorders (group FUN), infectious medical disorders (group INF) and noninfectious medical disorders (group MED), and surgical disorders (group SUR). Patients of groups INF and SUR were pooled into group INF+SUR to predict severe illness, and this group was compared with others with nonsevere illness. RESULTS: All patients exhibited neutrophilia, along with a neutrophil count that increased with illness severity. Lymphopenia, eosinopenia, and basopenia characterized patients of group INF+SUR. Neutrophilia, eosinopenia, and lymphopenia were independent predictors of the most severely affected patients. The association of a neutrophil count >9.0 × 109/L with lymphopenia (<1.4 × 109L) and eosinopenia (<0.04 × 109/L) had a specificity of 94.9% (95% confidence interval, 91.2%-97.1%) for inclusion in group INF+SUR, although with a low sensitivity (27.5%). CONCLUSION: Lymphocyte, eosinophil, and neutrophil counts should be considered in medical admissions of adults with abdominal pain. Lymphopenia associated with eosinopenia and significant neutrophilia is highly suggestive of a more severe illness.