title: Renal sarcoidosis: clinical, laboratory, and histologic presentation and outcome in 47 patients.
abstract: We conducted the current study to investigate the clinical, laboratory, and histologic features at presentation and the outcome of renal sarcoidosis (RS). Exhaustive retrospective data were collected by the French Sarcoidosis Group. Forty-seven adult patients were assessed (30 male/17 female, M/F ratio: 1.76). Median estimated glomerular filtration rate (eGFR) was 20.5 mL/min per 1.73 m(2) (range, 4-93 mL/min per 1.73 m(2)). Moderate proteinuria was found in 31 (66%) patients (median, 0.7 g/24 h; range, 0-2.7 g/24 h), microscopic hematuria in 11 (21.7%) patients, aseptic leukocyturia in 13 (28.7%) patients. Fifteen of 47 (32%) patients had hypercalcemia (>2.75 mmol/L). Eleven of the 22 (50%) patients diagnosed between June and September had hypercalcemia compared with only 4 of the 25 (16%) cases diagnosed during the other months (p < 0.001). Thirty-seven patients presented with noncaseating granulomatous interstitial nephritis (GIN), and 10 with interstitial nephritis without granulomas. Apart from hypercalcemia, the clinical phenotype was also remarkable for the high frequency of fever at presentation. All patients initially received prednisone (median duration, 18 mo), 10 received intravenous pulse methylprednisolone. eGFR increased from 20 +/- 19 to 44 +/- 24.7 mL/min per 1.73 m(2) at 1 month (p < 0.001, n = 38), to 47 +/- 19.9 mL/min per 1.73 m(2) at 1 year (p < 0.001, n = 46), to 49.13 +/- 25 mL/min per 1.73 m(2) at last follow-up (p < 0.001, n = 47). A complete response to therapy at 1 year and at last follow-up was strongly correlated with complete response at 1 month (p < 0.01). Renal function improvement was inversely related to initial histologic fibrosis score. A complete response to therapy at 1 year was strongly correlated with hypercalcemia at presentation (p = 0.003). Relapses were purely renal (n = 3) and purely extrarenal (n = 10) or both (n = 4), often a long time after presentation, with in some cases severe cardiac or central nervous system involvement. We conclude that hypercalcemia and fever at presentation are often associated with RS; RS is most often and permanently responsive to corticosteroid treatment, but some degree of persistent renal failure is highly frequent and its degree of severity in the long run is well predicted from both histologic fibrotic renal score and response obtained at 1 month.
authors.affiliation: From the Department of Internal Medicine (MM, PD, JPD), Department of Pathology (CC), Amiens Nord Hospital, Amiens; Department of Internal Medicine (MM), Université Paris 12, Assistance Publique-Hôpitaux de Paris, Henri Mondor Hospital, Créteil; Groupe Sarcoidose Francophone (MM, JJB, CC, JMN, JC, JPD, DV), Paris; Pulmonary Department (JMN, DV), Université Paris 13, EA 2363, Assistance Publique-Hôpitaux de Paris, Avicenne Hospital, Bobigny; Department of Infectious Disease (FXL), Department of Nephrology (JJB), Pulmonary Department (JC), Assistance Publique-Hôpitaux de Paris, Tenon Hospital, Paris; Department of Internal Medicine (VD), Assistance Publique-Hôpitaux de Paris, Beaujon Hospital, Clichy; Department of Nephrology (XB), CHI André Grégoire, Montreuil; Department of Internal Medicine (C. Chapelon, JCP), Assistance Publique-Hôpitaux de Paris, Pitié-Salpétrière Hospital, Paris; and Department of Nephrology (RM, GC), Amiens Sud Hospital, Amiens, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Mahévas
authors.forename: Francois Xavier
authors.initials: FX
authors.lastname: Lescure
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Boffa
authors.forename: Victoire
authors.initials: V
authors.lastname: Delastour
authors.forename: Xavier
authors.initials: X
authors.lastname: Belenfant
authors.forename: Catherine
authors.initials: C
authors.lastname: Chapelon
authors.forename: Carole
authors.initials: C
authors.lastname: Cordonnier
authors.forename: Raifat
authors.initials: R
authors.lastname: Makdassi
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Piette
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Naccache
authors.forename: Jacques
authors.initials: J
authors.lastname: Cadranel
authors.forename: Pierre
authors.initials: P
authors.lastname: Duhaut
authors.forename: Gabriel
authors.initials: G
authors.lastname: Choukroun
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Ducroix
authors.forename: Dominique
authors.initials: D
authors.lastname: Valeyre
mesh_terms: D058186:Acute Kidney Injury / Q000209:etiology; D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D016516:CD4-CD8 Ratio; D005260:Female; D005334:Fever / Q000209:etiology; D005355:Fibrosis; D005602:France; D005919:Glomerular Filtration Rate; D005938:Glucocorticoids / Q000627:therapeutic use; D006099:Granuloma / Q000209:etiology; D006417:Hematuria / Q000209:etiology; D006801:Humans; D006934:Hypercalcemia / Q000209:etiology; D007668:Kidney / Q000473:pathology; D007674:Kidney Diseases / Q000175:diagnosis* / Q000188:drug therapy; D007962:Leukocytes; D008218:Lymphocytosis / Q000209:etiology; D008297:Male; D008775:Methylprednisolone / Q000627:therapeutic use; D008875:Middle Aged; D009395:Nephritis, Interstitial / Q000209:etiology; D011241:Prednisone / Q000627:therapeutic use; D011507:Proteinuria / Q000209:etiology; D012189:Retrospective Studies; D012507:Sarcoidosis / Q000175:diagnosis* / Q000188:drug therapy; D014556:Urine / Q000166:cytology; D055815:Young Adult
chemical_list: D005938:Glucocorticoids; D011241:Prednisone; D008775:Methylprednisolone