Caravaca-Fontán Fernando, Shabaka Amir, Sánchez-Álamo Beatriz, de Lorenzo Alberto, Díaz Martha, Blasco Miquel, Rodríguez Eva, Sierra-Carpio Milagros, Malek Marín Tamara, Urrestarazú Andrés, Corona Cases Clara, Praga Manuel, Fernández-Juárez Gema
Department of Nephrology, Instituto de Investigación, Hospital Universitario 12 de Octubre, Madrid, Spain.
Department of Medicine, Universidad Complutense de Madrid, Madrid, Spain.
Clin Kidney J. 2020 Mar 11;14(1):197-204. doi: 10.1093/ckj/sfaa018. eCollection 2021 Jan.
Acute interstitial nephritis (AIN) is an emerging cause of acute kidney disease. While this disease usually follows an acute course, it may occasionally recur, representing a major challenge for the clinician.
We performed a retrospective, observational cohort study in 13 nephrology departments belonging to the Spanish Group for the Study of Glomerular Diseases. Patients with biopsy-proven AIN between 1996 and 2018 were included.
The study group consisted of 205 patients with AIN, 22 of which developed recurrent AIN (RAIN) after a median of 111 days from diagnosis. RAIN was due to a surreptitious reintroduction of a previously known implicated drug or toxic in six patients (27%), sarcoidosis in two (9%), Sjögren's syndrome in three (14%), light-chain-mediated AIN in two (9%) and tubulointerstitial nephritis and uveitis syndrome in two (9%), while in the rest of cases (32%), no precise cause could be identified. Microscopic haematuria was more frequent in patients with underlying systemic diseases. The first RAIN episode was treated with a repeated course of corticosteroids in 21 patients (95%). In six cases (27%), azathioprine and mycophenolate mofetil were added as corticosteroid-sparing agents. During a median follow-up of 30 months, 50 patients (27%) with no recurrences and 12 patients (55%) with RAIN reached Stages 4 and 5 chronic kidney disease (CKD). By multivariable logistic regression analysis, RAIN was independently associated with the risk of reaching Stages 4 and 5 CKD, even after adjusting for potential covariables.
RAIN is infrequent but is associated with poor kidney survival. RAIN should prompt clinicians to search for an underlying aetiology other than drug induced. However, in a large percentage of cases, no precise cause can be identified.
急性间质性肾炎（AIN）是急性肾疾病的一个新出现的病因。虽然这种疾病通常呈急性病程，但偶尔可能复发，这对临床医生来说是一个重大挑战。
我们在西班牙肾小球疾病研究组下属的13个肾脏病科进行了一项回顾性观察队列研究。纳入了1996年至2018年间经活检证实为AIN的患者。
研究组由205例AIN患者组成，其中22例在诊断后中位111天出现复发性AIN（RAIN）。RAIN的病因在6例患者（27%）中是先前已知的相关药物或毒物的隐匿性重新引入，2例（9%）为结节病，3例（14%）为干燥综合征，2例（9%）为轻链介导的AIN，2例（9%）为肾小管间质性肾炎和葡萄膜炎综合征，而在其余病例（32%）中，无法确定确切病因。镜下血尿在有潜在系统性疾病的患者中更常见。21例患者（95%）的首次RAIN发作采用重复疗程的皮质类固醇治疗。6例（27%）患者加用硫唑嘌呤和霉酚酸酯作为皮质类固醇节省剂。在中位30个月的随访期间，50例无复发患者（27%）和12例RAIN患者（55%）进展到4期和5期慢性肾脏病（CKD）。通过多变量逻辑回归分析，即使在调整潜在协变量后，RAIN仍与进展到4期和5期CKD的风险独立相关。
RAIN并不常见，但与肾脏存活率低相关。RAIN应促使临床医生寻找除药物诱导以外的潜在病因。然而，在很大一部分病例中，无法确定确切病因。
