[Pseudohyperkalemia and thrombocytosis]. / Pseudo-hyperkaliémie et thrombocytose.

INTRODUCTION: Hyperkalemia is common in medicine and requires rapid management. Besides the easily evoked causes such as renal failure, adrenal insufficiency, cell lysis or iatrogenic causes, false or pseudo-hyperkalemia should not be forgotten. OBSERVATIONS: Three patients (1 man, 2 women, aged 78, 84, 88) were managed for thrombocytosis (between 1306 and 2404 G/L) and non-symptomatic hyperkalemia (between 6.1 and 7.7mmol/L) are reported. Kalemia on blood collected in heparin tube was normal (4.4-4.6mmol/L). Therefore, no specific treatment for this pseudohyperkalemia was required. CONCLUSION: The combination of thrombocytosis and non-symptomatic hyperkalemia should suggest the diagnosis of pseudohyperkalemia and should prompt for a control of kalemia on blood collected in heparin tube. The recognition of this diagnosis is important in order to avoid unnecessary and potentially deleterious treatment of hyperkalemia.

[Cerebral infarction and tuberculosis: case report and literature review]. / Infarctus cérébral et tuberculose : rapport d'un cas et analyse de la littérature.

INTRODUCTION: Although tuberculous meningitis is an uncommon presentation of tuberculosis, it still remains one of the deadliest forms of this disease. In this context, the occurrence of a cerebral infarct is an aggravating factor. OBSERVATION: A 48-year-old Asian man presented himself in the emergency room for dysarthria and dysphagia of progressive onset. Cerebral CT showed a recent ischemic defect of the right internal capsule. Lumbar puncture showed meningitis with low sugar levels. Pulmonary micronodules on the thoracic CT suggested tuberculosis, which was confirmed by a broncho-alveolar lavage. Anti-tuberculosis treatment and early corticosteroid resulted in an improvement of the patient's state. CONCLUSION: Cerebral infarctions in patients with tuberculous meningitis are events that cannot be underestimated in terms of frequency or severity. Their poor prognosis is partly the result of insufficiently defined management, which combines anti-tuberculosis treatment and early corticosteroid therapy.

[An abscessed granulomatous prostatitis]. / Une prostatite granulomateuse abcédée.

INTRODUCTION: Prostatic abscesses are usually diagnosed in the setting of bacterial prostatitis. Rarely, they reveal or complicate granulomatous prostatitis. CASE REPORT: A 55-year-old man was admitted for acute urinary retention. Urine culture was sterile, with leukocyturia > 106/ml. After failure of antibiotic therapy with cefotaxime, CT scan revealed a necrotic prostatic collection and a nodular non-necrotic tissular lesion in the left upper lung lobe. Trans-rectal drainage of the prostatic lesion and lung biopsies revealed granuloma with multinucleated giant cells (without mycobacteria). The diagnosis of granulomatosis with polyangiitis was confirmed by high level of anti-proteinase 3 antibodies. Treatment with steroids and rituximab resulted in apyrexia, regression of the inflammatory syndrome and clinical manifestations. CONCLUSION: The diagnosis of granulomatosis with polyangiitis should be considered in the presence of a non-infectious granulomatous prostatitis with systemic involvement.

Concomitant association of giant cell arteritis and malignancy: a multicenter retrospective case-control study.

INTRODUCTION: Some studies suggest that there is an increased risk of malignancies in giant cell arteritis (GCA). We aimed to describe the clinical characteristics and outcomes of GCA patients with concomitant malignancy and compare them to a GCA control group. METHOD: Patients with a diagnosis of GCA and malignancy and with a maximal delay of 12 months between both diagnoses were retrospectively included in this study and compared to a control group of age-matched (3:1) patients from a multicenter cohort of GCA patients. RESULTS: Forty-nine observations were collected (median age 76 years). Malignancies comprised 33 (67%) solid neoplasms and 16 (33%) clonal hematologic disorders. No over-representation of a particular type of malignancy was observed. Diagnosis of GCA and malignancy was synchronous in 7 (14%) patients, while malignancy succeeded GCA in 29 (59%) patients. Malignancy was fortuitously diagnosed based on abnormalities observed in laboratory tests in 26 patients, based on imaging in 14 patients, and based on symptoms or clinical examination in the nine remaining patients. Two patients had a concomitant relapse of both conditions. When compared to the control group, patients with concomitant GCA and malignancy were more frequently male (p < 0.001), with an altered general state (p < 0.001), and polymyalgia rheumatica (p < 0.01). CONCLUSIONS: This study does not indicate an over-representation of any particular type of malignancy in GCA patients. Initial follow-up dictated by vasculitis may have led to an early identification of malignancy. Nevertheless, GCA male patients with an altered general state and polymyalgia rheumatica might more frequently show concomitant malignancies.

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.

[Retroperitoneal fibrosis in adults: Main characteristics and relevance of the diagnostic procedures based on a retrospective multicenter study on 77 cases]. / Fibrose rétropéritonéale de l'adulte : analyse descriptive et évaluation de la pertinence des examens complémentaires réalisés à visée diagnostique à partir d'une série rétrospective multicentrique de 77 cas.

INTRODUCTION: Retroperitoneal fibrosis (RPF) is a rare disorder characterized by the sheathing of retroperitoneal structures by fibro-inflammatory process. It can be either isolated or associated with an underlying disease or condition. In the absence of consistent and consensual approach, the objective of this study was to assess the relevance of diagnostic tests performed during the diagnostic work-up of RPF. METHODS: Seventy-seven patients were included in this retrospective multicenter study. The diagnosis of RPF was defined by the presence of a thickened circumferential homogeneous tissue unsheathing the infrarenal aorta, excluding peri-aneurysmal fibrosis and a clear evidence of a cancer. RESULTS: In 62 cases (80.5%), the RPF was considered as being primary or "idiopathic". Surgical (n=31) or CT-guided (n=9) biopsies of the RPF were performed in half of the patients showing some fibrotic or non-specific inflammatory lesions in 98% of cases. A bone marrow biopsy was performed in 23 patients leading to diagnosis of low grade B cell non-Hodgkin lymphoma in a single patient who also had a monoclonal gammopathy IgM. The systematic search for autoantibodies or serum tumor markers was of no diagnostic value. CONCLUSIONS: Although the diagnostic procedure was heterogeneous, no cause or associated disease was found in the majority of cases of FRP in this series. In the absence of any clinical or paraclinical evidence suggesting an underlying disease or any atypical features at presentation, a number of non-invasive tests (autoantibodies, tumor markers, bone scintigraphy) and also more invasive diagnostic tests (bone marrow and RPF biopsies) seem of little relevance.

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.

[Proteomics, a new tool for an accurate typing of amyloidosis]. / La protéomique, une nouvelle technique pour un typage optimal des amyloses.

Amyloidosis is a rare group of diseases related to extracellular deposition of proteins in an insoluble beta-pleated sheet structure presenting a characteristic apple-green birefringence under polarized light after Congo red staining. Thirty types of proteins are known to cause amyloidosis. The accurate identification of the amyloid protein is of paramount importance since it is a key step for the clinical management and personalized treatment. Amyloid typing is usually based on immunohistochemistry and immunofluorescence on tissular sections. This approach has several limits leading to a subtyping failure rate of 15 to 58% of cases. To overcome these difficulties, proteomic methods have been developed to characterize directly the amyloid protein. The most advanced technique carried out on fixed and paraffin-embedded tissue consists of laser microdissection followed by mass spectrometry. The type of amyloidosis can be determined in more than 95% of cases. However, the experience for this technique is very limited apart from the Mayo Clinic (Rochester, United States). In France, a very close proteomic assay has been implemented in the department of pathology of Foch Hospital with similar results. The introduction of proteomics in clinical practice represents a major improvement for typing amyloidosis. In this article, we discuss the benefits and limits of the different techniques used for amyloid classification and we briefly report our proteomic results.

[Vitamin D and autoimmunity. Second part: Clinical aspects]. / Vitamine D et auto-immunité. Deuxième partie : aspects cliniques.

Vitamin D is often confined to its role in calcium homeostasis and bone metabolism. An exponential literature discusses its non-skeletal effects, especially its central role in the physiology of the immune system, where it acts at several levels to maintain self-tolerance. Here, the authors review the experimental, epidemiological and clinical studies, illustrating the potential role of vitamin D in the development and perpetuation of autoimmune diseases such as systemic lupus erythematosus, type 1 diabetes mellitus, multiple sclerosis, inflammatory bowel diseases or rheumatoid arthritis.

[Vitamin D and autoimmunity. First part: Fundamental aspects]. / Vitamine D et auto-immunité. Première partie : aspects fondamentaux.

The effects of vitamin D on calcium homeostasis and bone metabolism are well known. In recent years, suboptimal vitamin D status has been recognized as a pandemic. Meanwhile, extra-skeletal effects of vitamin D are becoming better documented, particularly its effects on immunity. The authors present their actions on myeloid dendritic cells, T cells, B cells, as well as on the synthesis of antimicrobial peptides and autophagy, and the potential beneficial effects in autoimmune and inflammatory diseases.

[Spontaneous streptococcal arthritis of the pubic symphysis]. / Arthrites septiques spontanées à streptocoques de la symphyse pubienne.

Septic arthritis of the pubic symphysis is uncommon, and usually occurs in patients with predisposing conditions (female incontinence surgery, sports). Staphylococcus aureus and Pseudomonas aeruginosa are the main bacteria responsible of these infections. Streptococcal infections of the pubic symphysis are uncommon. We report three cases of streptococcal infections of the pubic symphysis that occurred in the absence of predisposing condition such as surgery or endocarditis. The diagnosis of septic arthritis was difficult, particularly in one patient who underwent an orchidopexy for a suspected of spermatic cord torsion before diagnosis was corrected. All three patients had a favourable outcome after an antibiotic treatment combining amoxicillin and rifampicin. Septic arthritis of the pubic symphysis should be suspected in patients with sudden groin pain, pubic tenderness and fever to avoid traumatic treatments and useless investigations.

[Hypereosinophilic syndromes: pathogenic and therapeutic up-to-date]. / Syndromes hyperéosinophiliques : actualités physiopathologiques et thérapeutiques.

The hypereosinophilic syndromes (HES), defined by an unexplained and sustained hypereosinophilia, can be associated with heterogeneous hematological conditions. Several molecular mechanisms underlying the eosinophilia, which remained indeterminate for a long time, have been recently identified. These recent advances allowed a better classification of the various forms of HES and the development of targeted therapies. The role of tyrosine kinases, especially PDGFRA, and the efficacy of tyrosine kinases inhibitors dramatically improved the diagnosis and the treatment of myeloproliferative variant of HES. On the other side, eosinophilia can be driven by IL-5 secreting abnormal and often clonal T cell subsets (lymphocytic variant of HES). The crucial role of this cytokine in eosinophil development, activation and survival leads to the assessment of anti-IL-5 monoclonal antibodies which have recently shown to provide a significant corticosteroid sparing effect in FIP1L1-PDGFRA negative HES patients. Despite these major advances, half of HES remains unexplained (idiopathic HES). Some FIPL1-PDGFRA negative patients respond to imatinib, suggesting the role of other tyrosine kinases (or other partners than FIP1L1 in a fusion gene implicating PDGFRA). Development of new biomarkers is needed to help physicians in the diagnosis, classification of HES and in the choice of a targeted therapy.