Repeat renal biopsy in a girl with tubulointerstitial nephritis and uveitis syndrome

A Japanese girl aged 8 years who presented with a 2-month history of uveitis subsequently developed tubulointerstitial nephritis. A percutaneous renal biopsy revealed massive interstitial mononuclear cell infiltrates consisting of CD4-positive T cells. Despite administration of topical corticosteroids, the ocular symptoms persisted. Systemic corticosteroid therapy dramatically reduced the ocular symptoms and urinary β₂-microglobulin (β 2MG) concentration. However, reducing the prednisolone dosage induced recurrence of uveitis associated with increased levels of urinary β 2MG. The CD4-positive T cell infiltration persisted in the second renal biopsy performed 6 months after the first renal biopsy. These observations suggest that the interstitial cell infiltration persists for a relatively long time in a proportion of patients with tubulointerstitial nephritis and uveitis syndrome (TINU). Although the renal outcome of TINU has been reported to be favorable, prolonged interstitial cell infiltration may affect long-term renal outcome. Selected patients with TINU should be followed with close observation. Received: 7 February 2001 / Revised: 8 June 2001 / Accepted: 27 June 2001     

Adult onset tubulointerstitial nephritis and uveitis syndrome

A Turkish woman aged 44 years who presented with a 1 month history of abdominal pain, fatigue and weight loss of 10 kg was diagnosed as having acute tubulointerstitial nephritis. Opthalmological evaluation revealed unilateral uveitis and contralateral chorioretinal scarring. X-ray films of the pelvis revealed unilateral sacroileitis. An elevated erythrocyte sedimentation rate, C-reactive protein, tubular proteinuria and renal glucosuria returned to normal 2 weeks after treatment was started. It is important to be aware of tubulointerstitial nephritis and uveitis syndrome in order to achieve a quick diagnosis in patients with renal impairment and tubular dysfunction with minor symptoms so that appropriate management can be started early.     

Hereditary coproporphyria and chronic tubulointerstitial nephritis

A 41-year-old woman was admitted to our hospital because of abdominal pain, limb weakness, and red-wine-colored urine. Laboratory data showed renal insufficiency and hyperchloremic metabolic acidosis due to type 4 renal tubular acidosis. Clinical manifestations and investigation of porphyrins in her urine, erythrocytes, and feces established the diagnosis of hereditary coproporphyria (HCP). Renal biopsy revealed chronic tubulointerstitial nephritis. She was treated with corticosteroid, but her renal function showed no improvement. Although rare, renal involvement has been described in several types of porphyrias other than HCP. Previously reported cases of porphyrias with renal histology share the findings of chronic tubulointerstitial nephritis. To our knowledge, this is the first report of a patient with HCP presenting with renal involvement. Received: February 21, 2000 / Accepted: June 28, 2000     

Pseudotumor cerebri following cyclosporine A treatment in a boy with tubulointerstitial nephritis associated with uveitis

An 11-year-old boy with recurrent nephritis due to tubulointerstitial nephritis associated with uveitis (TINU syndrome) was treated with cyclosporin A (CSA) to induce sustained remission. CSA was introduced as a steroid-sparing drug because of extreme obesity (body mass index 32 kg/m²). Although the boy did not complain of any clinical symptoms, eye inspection after 7 months revealed bilateral disk edema with retinal bleeding and the patient developed cerebrospinal hypertension. Pseudotumor cerebri was diagnosed by measuring the intracranial pressure (31 cmH₂O) and normal computer tomography and brain magnetic resonance imaging. Cessation of CSA therapy and treatment with mycophenolate mofetil led to resolution within 12 weeks.Supported by Forschungsunterstützungskreis Kindernephrologie e.V. Essen     

Acute tubulointerstitial nephritis following ingestion of Chlorella tablets

Here, we report on a boy with acute tubulointerstitial nephritis (ATIN), who developed it following ingestion of Chlorella tablets as a food supplement. He was incidentally detected to have glucosuria, proteinuria, and leukocyturia during school mass screening. He had had a history of ingestion of Chlorella tablets for 3 months. Laboratory studies showed anemia, increased levels of creatinine, decreased glomerular filtration rate (GFR), hypokalemia, hypo-uricemia, hypophosphatemia, hypergammaglobulinemia, proteinuria, leukocyturia, and glucosuria. ATIN was diagnosed by renal biopsy. The patient’s renal function improved after initiation of corticosteroid therapy and discontinuation of Chlorella for 6 months. Chlorella may be a causative allergen inducing tubulointerstitial injury in kidney.     

Predominant tubulointerstitial nephritis in a patient with systemic lupus nephritis

In most cases of systemic lupus erythematosus (SLE), glomerular lesions are the main renal complication. Although tubulointerstitial lesions are often associated with severe glomerular lesions, predominant or isolated tubulointerstitial injury in the presence of minimal glomerular abnormalities with SLE, so-called predominant tubulointerstitial lupus nephritis, is rare. Only ten cases are reported in the English literature. Herein, we describe the case of a 64-year-old man with SLE who presented with acute renal deterioration attributable to acute tubulointerstitial nephritis. Renal biopsy showed diffuse infiltration of inflammatory mononuclear cells in the interstitium and tubulitis without significant glomerular lesions. Immunofluorescence study revealed positive staining for IgG, C3, and C1q along the renal tubular basement membrane (TBM). Electron microscopy also showed electron-dense deposits in the TBM. Other causes of tubulointerstitial injury, such as drug use and infection, were ruled out. Taking these findings together with the presence of antitubular basement membrane antibody, predominant tubulointerstitial lupus nephritis was diagnosed. Treatment with oral corticosteroids for 6 weeks improved renal function. Even after tapering of the corticosteroid, renal function and serological markers of SLE activity have remained stable in this patient for more than 12 months.     

Distal tubular dysfunction in lupus nephritis of childhood and adolescence

We describe a girl with lupus nephritis who presented with distal renal tubular acidosis and hyporeninemic hypoaldosteronism. While distal tubular dysfunction is well recognized in adult systemic lupus erythematosus (SLE), only a few pediatric patients have been reported. Evaluation of five pediatric patients with SLE revealed that distal tubular dysfunction in childhood and adolescence is rare. Received: 17 December 1998 / Revised: 30 March 1999 / Accepted: 30 March 1999     

Tubulointerstitial nephritis and uveitis in monozygotic twin boys

We describe monozygotic male twins who developed tubulointerstitial nephritis and uveitis (TINU) almost 2 years apart. They presented with non-specific symptoms and were noted to have glycosuria and renal impairment. Both children have uveitis. One had biopsy-proven interstitial nephritis and the other had biochemical evidence of transient tubular dysfunction. While the renal parameters improved, they are still under treatment for uveitis. The occurrence of TINU in identical twins at an interval of just under 2 years supports a strong genetic element in the aetiology of this syndrome. We believe this is the first report of male twins with TINU.     

Tubulointerstitial nephritis and uveitis syndrome associated with hyperthyroidism

We report a 17-year-old male patient with tubulointerstitial nephritis and uveitis (TINU) associated with hyperthyroidism. He presented with a 2-month history of fatigue, loss of appetite, low-grade fever, and a 12-kg weight loss when he was admitted to our hospital. He had iritis, which was complicated by fibrin in the anterior chamber, diagnosed by slit-lamp examination. On laboratory examinations, deteriorated renal function (blood urea nitrogen level was 25.9 mg/dl and creatinine level was 2.82 mg/dl) and elevated urinary levels of N-acetyl-β-D-glucosaminidase (33.1 U/l) and β2-microglobulin (78 600 μg/l) were observed. Serum thyroid-stimulating hormone (TSH) was undetectable, at less than 0.01 μIU/ml, and free triiodothyronine and free thyroxine were elevated, up to 5.23 pg/ml and 2.85 ng/dl, respectively. The titers of antithyroglobulin and antithyroid microsomal and TSH-receptor antibodies were not elevated. Abdominal and thyroidal ultrasonography showed evident bilateral enlargement of the kidneys and diffuse enlargement of the thyroid gland. Iodine-123 scintigraphy showed low uptake in the thyroid gland. The biopsied renal specimen showed mild edema and severe diffuse infiltration of mononuclear cells and few eosinophils in the interstitium, without any glomerular or vascular abnormalities. Based on the clinical features and pathological findings, a diagnosis of TINU syndrome with associated hyperthyroidism was made. Treatment was started with 30 mg/day of prednisolone. The iritis disappeared, and the patient's clinical status improved remarkably. This case suggests the possibility of thyroid dysfunction in some patients with TINU syndrome, and we believe thyroid function should be measured in all TINU patients. Moreover, histopathological diagnosis of the thyroid glands before treatment is necessary for TINU patients with thyroid dysfunction.     

Serial renal biopsies in three girls with tubulointerstitial nephritis and uveitis syndrome

Tubulointerstitial nephritis and uveitis (TINU) syndrome is considered to have a good prognosis even without any immunosuppressive therapy, although there is no histological evidence to support this. The objective of this study was to evaluate, retrospectively, serial renal biopsy findings in three girls with TINU syndrome who were treated with prednisolone. At presentation, all patients had significantly elevated urinary β₂-microglobulin levels (7583–19,313 μg/l) and high serum creatinine levels (0.93–1.3 mg/dl). The elevated β₂-MG and creatinine levels persisted for 1 month, and renal biopsies were performed to establish a definitive diagnosis. The initial biopsy specimens of all patients revealed marked interstitial enlargement consisting of infiltration of lymphocytes; there was also notable tubulitis and infiltration of eosinophils. All patients received prednisolone therapy following the diagnosis. A second renal biopsy was performed 9 months after the first biopsy for two of three patients, and 2 years later for the third patient. The biopsy specimens taken at 9 months still showed histological changes of acute inflammation; in contrast, that taken at 2 years showed a lower degree of acute inflammation, but scar formation was observed in some regions. Based on these results, we conclude that selected TINU syndrome patients require some immunosuppressive therapy.     

Acute interstitial nephritis presenting as presumed minimal change nephrotic syndrome

Nephrotic syndrome (NS) secondary to drug-induced acute interstitial nephritis (AIN) is well described in adult but is very rare in children. We report an unusual case of AIN mimicking prototypical childhood minimal change NS. A 2-year-old girl on long-standing amoxicillin therapy for vesicoureteral reflux presented with the acute onset of generalized edema, proteinuria, hypoalbuminemia, hypercholesterolemia, and an inactive urinary sediment. She was placed on empiric steroid therapy for presumed minimal change NS. When she did not respond to steroids, a renal biopsy was performed and revealed AIN. Her NS resolved completely with cessation of her amoxicillin therapy and concomitant tapering of her steroids. This patient demonstrates that the association of AIN with NS should be carefully considered in children on antimicrobials who develop NS, even in the absence of the classic clinical features of AIN. In addition to the usual work-up and care of a child with NS, in these patients consideration may also need to be given to withdrawal of the potential precipitating agent. Received September 23, 1997; received in revised form February 3, 1998; accepted February 4, 1998     

Acute tubulointerstitial nephritis in association withYersinia pseudotuberculosis infection

A 4-year-old girl was diagnosed as having acute renal failure due to tubulointerstitial nephritis. The girl presented with remittent fever. vomiting and non-oliguric acute renal failure with sterile pyuria and tubular reabsorptive dysfunction. Ultrasound examination revealed that the kidneys were markedly enlarged with diffuse hyperechogenicity in the cortex when the abnormal renal function was present and were restored in size and echogenicity when the renal function normalised. A diagnosis ofYersinia pseudotuberculosis infection was based on a rise in haemagglutination titres against the organism.     

Cytokine upregulation in tubulointerstitial nephritis associated with membranous nephropathy

We describe the upregulation of cytokines in a 45-year-old woman with tubulointerstitial nephritis and membranous nephropathy revealed by renal biopsy. She was treated with a combination of prednisolone and cyclosporin. Histological findings showed appreciable improvement, and urinary protein excretion was decreased from 15 g/day to 1 g/day. Elevated urinary levels of chemokines, interleukin (IL)-8 and monocyte chemotactic and activating factor (MCAF)/monocyte chemoattractant protein (MCP)-1, and serum levels of tumor necrosis factor (TNF)-α decreased during convalescence; 13 other patients with membranous nephropathy did not show elevation of these cytokines. These results suggest that the upregulation of these cytokines may participate in the pathogenesis of tubulointerstitial nephritis and that combination therapy of prednisolone and cyclosporin may be effective, possibly via inducing a decrease in these cytokines. Received: May 6, 1998 / Accepted: October 9, 1998     

A syndrome of acute interstitial nephritis and anterior uveitis

A syndrome of acute interstitial nephritis (AIN) and anterior uveitis is described in two children and the literature is reviewed. These disorders appear to improve, in uncontrolled studies, with systemic and topical ophthalmic corticosteroid treatment. Although the renal and ocular prognoses appear good, it is important to recotnize that patients with AIN are at risk for uveitis and if present, consultation with an ophthalmologist is recommended.     

Cimetidine-induced tubulointerstitial nephritis with both MPO-ANCA and PR3-ANCA

We describe a 75-year-old man with tubulointerstitial nephritis (TIN) with myeloperoxidase (MPO)-antineutrophil antibody (ANCA) and proteinase-3 (PR3)-ANCA. He had a slight fever and eruption with itching after taking cimetidine (prescribed after gastrectomy for gastric cancer) and he was admitted to a nearby hospital. There, he showed proteinuria, serum creatinine (sCr) of 2.9 mg/dl, and creatinine clearance (Ccr) of 44 ml/min per 1.73 m². His MPO-ANCA titer was 267 EU, and PR3-ANCA titer was 112 EU. Abnormal concentrations in bilateral kidneys were found by gallium scintigraphy. For these reasons, he was transferred to our hospital. Percutaneous renal biopsy was performed after admission. Severe tubular atrophy, mild interstitial fibrosis, and severe mononuclear cell infiltration of the interstitium were noted. Drug-induced renal impairment was suspected, and cimetidine administration was withdrawn. Lymphocyte stimulation tests (DLSTs) were performed. The cimetidine titer was positive, at 2,537 cpm. After the withdrawal of cimetidine, the PR3-ANCA titer was reduced gradually, and, next, the MPO-ANCA titer was also reduced. The sCr level was reduced to 1.2 mg/dl. In summary, we report herein the first case of cimetidine-induced TIN associated with both MPO-ANCA and PR3-ANCA.     

Tubulointerstitial nephritis and uveitis: an immunological disorder?

A 14-year-old boy with tubulointerstitial nephritis and uveitis (TINU syndrome) is described. Nephropathy improved without systemic cortisone treatment, whereas uveitis relapsed and was treated with topical steroids. Blood cell immunological analysis and serum analysis revealed signs of cytotoxic T-cell, macrophage and granulocyte activation, which declined as the clinical symptoms improved. This may be interpreted as an indication of their significance as markers in the pathogenesis of this syndrome or as part of a microbial-triggered immune response.