Ciprofloxacin-induced granulomatous interstitial nephritis and localized elastolysis

Evidence of Tosufloxacin Deposition in the Kidneys of a Patient Presenting with Crystal Nephropathy

Tosufloxacin tosilate is classified as a new quinolone antibacterial agent, which has been reported to cause crystal nephropathy. However, the origin of these crystal deposits has not yet been elucidated. We encountered a case of renal failure that progressed slowly owing to crystal-forming interstitial nephritis after long-term exposure to tosufloxacin. Mass spectrometry of the renal specimens revealed that tosufloxacin was deposited in the kidneys. The patient's renal function improved slowly with the withdrawal of tosufloxacin and steroid therapy. This is the first case to demonstrate the presence of crystal deposits consisting of tosufloxacin.

An imine-linked covalent organic framework for renewable and sensitive determination of antibiotic

Lanthanide-functionalized porous organic materials have been the promising candidates in the chemical and biological sensing. Considering the superior thermal and solvent stability of covalent organic frameworks (COFs), the development of lanthanide ions-functionalized COFs based sensing platform is meaningful, while remains to be a challenge. In this work, a new imine-linked COF which provides suitable coordination sites for Tb³⁺ was constructed via the Schiff base reaction between P-phenylenediamine (Pda) and 2,6-Diformylpyridine (Dfp). Benefiting from its high signal-to-noise, the COF@Tb shows excellent ability to determinate ciprofloxacin (CIP) with a detection limit of 3.01 nM. The measurement can maintain good stability in the presence of potential interference or in actual sample. Being washed with ethanol after each measurement, COF@Tb can be recycled for five times. This work provides a novel alternative strategy for efficient construction of lanthanide-grafted COFs and may promote the development of porous organic materials based chemical sensing.

A turn-on fluorescence probe Eu3+ functionalized Ga-MOF integrated with logic gate operation for detecting ppm-level ciprofloxacin (CIP) in urine

The threatening of antibiotic drugs for human and environment is being paid more and more attention. Ciprofloxacin (CIP), a strong quinolone antibiotic drug widely used in therapeutic treatments, is the most frequently detected in surface waters among the fluoroquinolones, which represents animal and human health risks. A novel highly fluorescent Ga-based hybrid (Eu³⁺@1) has been synthesized based on metal-organic framework (MOF) by encapsulating lanthanide cations Eu³⁺ in its channels. The as-synthesized compound possesses excellent water and pH-independent stability. It displays week red luminescence of Eu³⁺ in itself and can sense the CIP concentration as turn-on fluorescent probe in the human urine. With addition of CIP, the evident luminescence enhancement is clearly observed from the Eu³⁺@1. Linear correlation between the fluorescence intensity and the concentration of CIP is investigated, proving the excellent performance of Eu³⁺@1 in the detection of CIP with linear range (0.01-0.2 mg/mL) and low detection limit (2.4 ppm or 2.4 μg/mL). The response time is also very quick, less than 3 min. Based on these findings, we introduce AND logic gate strategy to the probe. The input of the logic gates (0, 1), (0, 1, 1), (1, 1, 1) cause the different outputs of CIP determination "LOW" (<25 ppm),"NORMAL" (25-76 ppm), "HIGH" (>76 ppm), respectively. The novel strategy can be applied for a real-time CIP concentration evaluation by intelligent discrimination.

Clinical Manifestations and Outcomes of Fluoroquinolone-Related Acute Interstitial Nephritis

OBJECTIVE

To describe the clinical presentation, diagnosis, and outcomes of patients with biopsy-proven acute interstitial nephritis (AIN) related to fluoroquinolone (FQ) therapy.

PATIENT AND METHODS

We conducted a retrospective review of biopsy-proven AIN attributed to FQ use at Mayo Clinic's campus in Rochester, Minnesota, from January 1, 1993, through December 31, 2016. Cases were reviewed by a renal pathologist and attributed to FQ use by an expert nephrologist. We also reviewed and summarized all published case reports of biopsy-proven AIN that were attributed to FQ use.

RESULTS

We identified 24 patients with FQ-related biopsy-proven AIN at our institution. The most commonly prescribed FQ was ciprofloxacin in 17 patients (71%), and the median antibiotic treatment duration was 7 days (interquartile range [IQR], 5-12 days). The median time from the initiation of FQ to the diagnosis of AIN was 8.5 days (IQR, 3.75-20.75 days). Common clinical manifestations included fever (12; 50%), skin rash (5; 21%), and flank pain (2; 8%), and 9 (38%) had peripheral eosinophilia. However, 4 (17%) of the patients were asymptomatic at the time of diagnosis and AIN was suspected on the basis of routine laboratory monitoring. Most patients (17; 71%) recovered after the discontinuation of antibiotic therapy, and renal function returned to baseline at a median of 20.5 days (IQR, 11.75-27.25 days). Six patients (25%) required temporary hemodialysis, and 14 patients (58%) received corticosteroid therapy.

CONCLUSION

The onset of FQ-related AIN can be delayed, and a high index of suspicion is needed by physicians evaluating these patients. Overall outcomes are favorable, with recovery to baseline renal function within 3 weeks of discontinuing the offending drug.

Histopathologic review of granulomatous inflammation

Granulomatous inflammation is a histologic pattern of tissue reaction which appears following cell injury. Granulomatous inflammation is caused by a variety of conditions including infection, autoimmune, toxic, allergic, drug, and neoplastic conditions. The tissue reaction pattern narrows the pathologic and clinical differential diagnosis and subsequent clinical management. Common reaction patterns include necrotizing granulomas, non necrotizing granulomas, suppurative granulomas, diffuse granulomatous inflammation, and foreign body giant cell reaction. Prototypical examples of necrotizing granulomas are seen with mycobacterial infections and non-necrotizing granulomas with sarcoidosis. However, broad differential diagnoses exist within each category. Using a pattern based algorithmic approach, identification of the etiology becomes apparent when taken with clinical context. The pulmonary system is one of the most commonly affected sites to encounter granulomatous inflammation. Infectious causes of granuloma are most prevalent with mycobacteria and dimorphic fungi leading the differential diagnoses. Unlike the lung, skin can be affected by several routes, including direct inoculation, endogenous sources, and hematogenous spread. This broad basis of involvement introduces a variety of infectious agents, which can present as necrotizing or non-necrotizing granulomatous inflammation. Non-infectious etiologies require a thorough clinicopathologic review to narrow the scope of the pathogenesis which include: foreign body reaction, autoimmune, neoplastic, and drug related etiologies. Granulomatous inflammation of the kidney, often referred to as granulomatous interstitial nephritis (GIN) is unlike organ systems such as the skin or lungs. The differential diagnosis of GIN is more frequently due to drugs and sarcoidosis as compared to infections (fungal and mycobacterial). Herein we discuss the pathogenesis and histologic patterns seen in a variety of organ systems and clinical conditions.

Renal allograft granulomatous interstitial nephritis: observations of an uncommon injury pattern in 22 transplant recipients

Background: Granulomatous interstitial nephritis (GIN) is uncommon in native kidneys, and descriptions in allografts are few. We report clinical and pathologic findings in 22 allograft recipients with GIN identified in renal allograft biopsies and nephrectomies.

Methods: Renal allografts with GIN were retrieved from the pathology files of two academic medical centers. Available clinical and pathologic data were compiled retrospectively for a 23-year period.

Results: GIN was present in 23 specimens from 22 patients (15 males and 7 females) with allograft dysfunction [serum creatinine averaged 3.3 mg/dL (range 1.4–7.8)], at a mean age of 48 years (range 22–77). GIN was identified in 0.3% of biopsies at a mean of 552 days post transplantation (range 10–5898). GIN was due to viral (5), bacterial (5) and fungal (2) infections in 12 (54.5%), and drug exposure was the likely cause in 5 cases (22.7%). One had recurrent granulomatosis with polyangiitis. In 4 cases, no firm etiology of GIN was established. Of 18 patients with follow up data, 33.3% had a complete response to therapy, 44.5% had a partial response and 22.2% developed graft loss due to fungal and E. coli infections. All responders had graft survival for more than 1 year after diagnosis of GIN.

Conclusions: Allograft GIN is associated with a spectrum of etiologic agents and was identified in 0.3% of biopsies. Graft failure occurred in 22% of this series, due to fungal and bacterial GIN; however, most had complete or partial dysfunction reversal and long–term graft survival after appropriate therapy.

Acute Ciprofloxacin-Induced Crystal Nephropathy with Granulomatous Interstitial Nephritis

Crystal-induced acute kidney injury (AKI) is caused by the intratubular precipitation of crystals, which results in obstruction and kidney injury. Ciprofloxacin, a commonly used antibiotic, causes AKI secondary to immune-mediated interstitial injury. Rare mechanisms of ciprofloxacin-induced renal injury include crystalluria, rhabdomyolysis, and granulomatous interstitial nephritis. Clinical and experimental studies have suggested that crystalluria and crystal nephropathy due to ciprofloxacin occur in alkaline urine. Preexisting kidney function impairment, high dose of the medication, and advanced age predispose to this complication. We report a case of ciprofloxacin-induced crystal nephropathy and granulomatous interstitial nephritis in a young patient with no other predisposing factors. The patient responded to conservative treatment without the need for glucocorticoids.

Chemical-Induced Nephropathy: A Review of the Renal Tubulointerstitial Lesions in Humans

It is almost ironic that one of the major organs that serves to maintain the “internal milieux” by secretion of various toxic agents, can itself become injured in the process. The pattern of morphologic renal injury is nonspecific and can involve any of the components of the kidney, although the injury and subsequent morphologic changes are most commonly noted in the tubules and/or interstitium. Of course, unless the drug/toxin is commonly or regularly noted to be associated with tubular and/or interstitial injury, the association of the drug with the renal changes may be missed and the correlation may not necessarily identify causation. For example, if a drug is associated with a renal injury in a given individual, it may be quite difficult to prove that the drug is the cause of the injury. This scenario is somewhat reminiscent of the test question—is it “true-true-related,” or “true-true-unrelated”? Sometimes it is only by the accrual of a great many examples or correlations, and or dissection of the pathophysiology, can it be shown that the drug is directly related to the observed morphologic (and subsequent clinical) injury. Renal changes induced by chemicals can affect the tubules, interstitium or both. This review of chemically induced nephropathy in humans considers acute tubular necrosis, interstitial nephritis , and tubulointerstitial nephritis or nephropathy. Because the tubules and the interstitium are so intimately related, injury to 1 of these 2 components may eventually lead to injury of the other, resulting in tubulointerstitial disease.

Granulomatous Interstitial Nephritis: A Clinicopathologic Study of 46 Cases from a Single Institution

Acute interstitial nephritis is commonly seen in kidney biopsies of patients with acute renal failure; however, granulomatous interstitial nephritis (GIN) is rare. We identified 46 cases of GIN in a 17-year period in this institution and we investigated their most probable etiologies. Complete clinical information was available in 38 patients. Seventeen of 38 patients (44.7%) were classified as drug-induced. Renal sarcoidosis was responsible for 28.9% of cases, and the remaining 15.9% of cases included Wegeners granulomatosis, foreign body giant cell reaction, GIN secondary to intravesical bacillus Calmette-Guerin therapy for bladder cancer, and xanthogranulomatous pyelonephritis. Clinical investigation failed to reveal possible etiology in 4 patients (10.5%), classified as idiopathic. We concluded that three quarters of our cases were either drug-induced or due to sarcoidosis; only a small proportion of our cases occurred secondary to any other cause or to unknown factors.

Granulomatous interstitial nephritis

Granulomatous interstitial nephritis (GIN) is a rare entity detected in ∼0.5-0.9% of all renal biopsies. GIN has been linked to several antibiotics such as cephalosporins, vancomycin, nitrofurantoin and ciprofloxacin. It is also associated with NSAIDs and granulomatous disorders such as sarcoidosis, tuberculosis, fungal infections, and granulomatosis with polyangiitis. Renal biopsy is critical in establishing this diagnosis, and the extent of tubular atrophy and interstitial fibrosis may aid in determining prognosis. Retrospective data and clinical experience suggest that removal of the offending agent in conjunction with corticosteroid therapy often results in improvement in renal function. We describe a patient with a history of multiple spinal surgeries complicated by wound infection who presented with confusion and rash with subsequent development of acute kidney injury. Urinalysis demonstrated pyuria and eosinophiluria, and renal biopsy revealed acute interstitial nephritis with granulomas. These findings were attributed to doxycycline treatment of his wound infection. This review explores the clinical associations, presentation, diagnosis, and treatment of this uncommon cause of acute kidney injury.

Risk of acute kidney injury associated with the use of fluoroquinolones

BACKGROUND

Case reports indicate that the use of fluoroquinolones may lead to acute kidney injury. We studied the association between the use of oral fluoroquinolones and acute kidney injury, and we examined interaction with renin-angiotensin-system blockers.

METHODS

We formed a nested cohort of men aged 40-85 enrolled in the United States IMS LifeLink Health Plan Claims Database between 2001 and 2011. We defined cases as men admitted to hospital for acute kidney injury, and controls were admitted to hospital with a different presenting diagnosis. Using risk-set sampling, we matched 10 controls to each case based on hospital admission, calendar time (within 6 wk), cohort entrance (within 6 wk) and age (within 5 yr). We used conditional logistic regression to assess the rate ratio (RR) for acute kidney injury with current, recent and past use of fluoroquinolones, adjusted by potential confounding variables. We repeated this analysis with amoxicillin and azithromycin as controls. We used a case-time-control design for our secondary analysis.

RESULTS

We identified 1292 cases and 12 651 matched controls. Current fluoroquinolone use had a 2.18-fold (95% confidence interval [CI] 1.74-2.73) higher adjusted RR of acute kidney injury compared with no use. There was no association between acute kidney injury and recent (adjusted RR 0.87, 95% CI 0.66-1.16) or past (RR 0.86, 95% CI 0.66-1.12) use. The absolute increase in acute kidney injury was 6.5 events per 10 000 person-years. We observed 1 additional case per 1529 patients given fluoroquinolones or per 3287 prescriptions dispensed. The dual use of fluoroquinolones and renin-angiotensin-system blockers had an RR of 4.46 (95% CI 2.84-6.99) for acute kidney injury. Our case-time-control analysis confirmed an increased risk of acute kidney injury with fluoroquinolone use (RR 2.16, 95% CI 1.52-3.18). The use of amoxicillin or azithromycin was not associated with acute kidney injury.

INTERPRETATION

We found a small, but significant, increased risk of acute kidney injury among men with the use of oral fluoroquinolones, as well as a significant interaction between the concomitant use of fluoroquinolones and renin-angiotensin-system blockers.

[Granulomatous interstitial nephritis: A retrospective study of 44 cases]

PURPOSE

Granulomatous interstitial nephritis (GIN) are identified in 0.5 to 1,3% of all renal biopsies. Renal outcome and treatment modalities are not clearly established in the literature.

METHODS

We retrospectively analyzed a case series of 44 GIN identified among all renal biopsies performed between 1984 and 2005 in the Rhône-Alpes area.

RESULTS

The study population included 25 men and 19 women with a mean age of 56 years, and mean diagnostic delay was 11 months. Renal function was severely impaired (mean creatinine clearance 24mL/min). Proteinuria was observed in 77% (mean value 0,9 g/24h) of the patients and associated with microscopic hematuria and leukocyturia in 30% and 25%, respectively. The most common diagnosis was sarcoidosis (25%, n = 11), followed by drug-induced GIN (9%, n = 4), tuberculosis (6,8%, n=3), hemopathy-related paraneoplastic GIN (6,8%, n = 3), HIV infection (n = 1) and chronic renal allograft rejection (n = 1). In other patients, no aetiology was found (48%, n = 21). Severity of renal failure justified hemodialysis in 34% (n = 15) of the patients. Three patients underwent renal transplantation. Nonetheless, renal outcome was generally favorable: renal function improved in 41% (n = 18) and stabilized in 34% (n = 15) of patients.

CONCLUSIONS

Sarcoidosis, drug-induced and infections represent the main causes of GIN. Histologic features are not specific enough to determine the aetiology. Corticosteroids is the gold standard in sarcoidosis, drug-induced, and idiopathic GIN. Treatment is etiologic in the other cases.

Renal granulomatoses: a retrospective study of 40 cases and review of the literature

Renal granulomatoses represent 0.5%-0.9% of nephropathies examined by renal biopsies. Granulomas can be isolated to the kidney or associated with other tissue involvement. We describe 40 consecutive patients with renal granulomatoses, associated with pauci-immune crescentic glomerulonephritis in 2 patients and with vasculitis in another, seen in northeastern Paris hospitals between January 1991 and February 2004. The criterion for inclusion was the presence of 1 or more epithelioid granulomas in the renal interstitium. Our population of 25 men and 15 women had a median age of 53 years. All patients suffered from renal insufficiency with median creatininemia of 236.8 micromol/L (range, 124-805 micromol/L), associated with hypertension (25%), median proteinuria of 0.6 g/24 h (range, 0.08-3.00 g/24 h), microscopic hematuria (15%) and leukocyturia (22.5%). Histologic examination of extrarenal specimens detected granulomas in 82.4% of the bronchial biopsies taken, and in 100% of the 2 skin biopsies, the 2 lymph-node biopsies, and the liver and colon biopsies. The following etiologies were retained: sarcoidosis for 20 (50%) patients, drug-induced for 7 (17.5%), tuberculosis for 3 (7.5%), Wegener granulomatosis for 2 (5%), and leprosy, Mycobacterium avium infection, and Crohn disease for 1 (2.5%) patient each. No etiology could be identified for 5 (12.5%) patients. Treatment must be adapted to the etiology of each case. The renal outcome after treatment was generally favorable, with the estimated median creatinine clearance increasing from 26 mL/min (range, 5.4-80.0 mL/min) to 46.5 mL/min (range, 0-118 mL/min) after a median follow-up of 35.5 months (range, 3-158 mo). Nonetheless, 32 patients had persistent renal insufficiency; 1 required hemodialysis and another underwent renal transplantation. Sarcoidosis and medications are the most common causes of renal granulomatosis. Idiopathic and drug-induced forms do not relapse after treatment discontinuation, and remission persists at long-term follow-up.

Acute granulomatous interstitial nephritis secondary to bisphosphonate alendronate sodium

Chronic lymphocytic leukemia (CLL) is the most common leukemia in the Western world and is characterized by a progressive accumulation of functionally incompetent monoclonal lymphocytes. Renal involvement has been described in CLL but is uncommon. Granulomatous interstitial nephritis is a rare but characteristic hallmark of certain diseases such as sarcoidosis and tuberculosis. These epithelial reactions have also been reported with medications, infections, inflammation, Wegener's granulomatosis, and jejunoileal bypass. We present a 74-year-old woman with a stage 0 chronic lymphocytic leukemia who developed acute renal failure following the initiation of alendronate. The renal biopsy revealed an acute granulomatous interstitial nephritis. Infectious and inflammatory etiologies were ruled out. Hemodialysis was required despite discontinuation of all medications. Partial recovery of renal function occurred after 6 weeks of prednisone therapy and cyclophosphamide. This report describes a unique case of acute granulomatous interstitial nephritis and leukemic cell kidney infiltration by CLL.

Les insuffisances rénales aiguës aux quinolones. Revue générale à propos d'une observation avec cristallisation liée à la ciprofloxacine

A 58 year-old woman developed an acute renal failure very quickly after ingestion of two 500 mg tablets of ciprofloxacin, without any other identifiable risk factor. Renal biopsy was performed. No sign of acute interstitial nephritis was observed but tubular lesions were found, accompanied by deposits of a brown-yellowish substance identified by infrared microscopy as a ciprofloxacin salt. The outcome was favourable. This observation gives the opportunity to remind the different forms of quinolone-induced renal injury and to discuss the possible ways for preventing renal side-effects related to the quinolone use.

Quinolone hypersensitivity

PURPOSE OF REVIEW

Quinolones are potent antibacterial agents that can cause drug hypersensitivity reactions affecting different organs. A better understanding of the underlying mechanism and the level of crossreactivity within different quinolones is needed to handle and prevent these diseases.

RECENT FINDINGS

The adverse side-effects caused by quinolones are the result of different immunological mechanisms and cause quite different diseases. The development of an assay detecting quinolone-specific IgE revealed specific antibodies in more than 50% of patients with immediate-type reactions, and the majority of sera also reacted with related compounds. In maculopapular drug exanthemas caused by ciprofloxacin, specific T cells could be detected and cloned. They reacted with ciprofloxacin directly, and crossreactivity to related compounds was detected in approximately 50% of the clones.

SUMMARY

Quinolones can cause drug hypersensitivity reactions by different immunological mechanisms. In-vitro analysis suggests that crossreactivity is common.

Nephrotoxicity and purpura associated with levofloxacin

OBJECTIVE

To report a patient with lung cancer and idiopathic myelofibrosis with myeloid metaplasia who developed purpura and acute renal failure while receiving levofloxacin, and review the existing literature on quinolone nephrotoxicity.

CASE SUMMARY

A 73-year-old white man, with a medical history of non-small-cell lung cancer and idiopathic myelofibrosis with myeloid metaplasia, was prescribed levofloxacin because of a lower urinary tract infection. Three days later, he presented with palpable purpura and erythematous skin lesions over the lower limbs and trunk, with a markedly reduced urinary output. Serum creatinine and urea nitrogen were 6.4 and 190 mg/dL, respectively. Levofloxacin was discontinued, and prednisone, furosemide, and intravenous fluids were given. The patient fully recovered over the ensuing 4 weeks.

CONCLUSIONS

Nephrotoxicity associated with levofloxacin is uncommon. Allergic interstitial nephritis or vasculitis is believed to be the underlying pathologic process. Definitive diagnosis requires performance of renal biopsy, although this is not always feasible. In this case, a return of renal function to normal, with the disappearance of purpura following the discontinuation of levofloxacin and corticosteroid treatment, supports the presumptive diagnosis of a hypersensitivity reaction to levofloxacin.

Granulomatous tubulointerstitial nephritis in the renal allograft

Granulomatous tubulointerstitial nephritis has rarely been described in renal allografts. Of 1,574 renal allograft tissue specimens obtained from 514 patients in the period 1993 to 1998, we report three cases (0.6%) with interstitial nephritis containing multiple noncaseating granulomas. Biopsy specimen 1 was obtained from a 44-year-old woman with a 6-day history of systemic Candida albicans infection and showed multiple granulomas containing budding yeasts. Biopsy specimen 2 was from a 33-year-old man who presented with miliary spread of Mycobacterium tuberculosis 12 days before the allograft biopsy. Biopsy specimen 3 was from a 23-year-old woman who presented with Escherichia coli urinary infection and bacteremia that was treated with antibiotics for 10 days before the biopsy. Granulomatous inflammation in reponse to infectious agents or drugs in immunosuppressed kidney transplant recipients can rarely give rise to allograft interstitial nephritis that is distinct from acute rejection. To our knowledge, there are no prior reports of granulomatous tubulointerstitial nephritis associated with C albicans and E coli infection or antibiotic therapy in human renal allografts.

Fluoroquinolones in pediatrics and their nephrotoxicity in adults: minireview

In recent years there is increasing pressure to use fluoroquinolones in pediatric patients but relatively few data have been published in the literature. Therefore this paper reviews the available information about the pharmacokinetics of fluoroquinolones in children and their use in pediatric urinary tract infections, taking into account their potential as nephrotoxic agents. From the available data it seems reasonable to suggest that there is no risk of quinolone-induced nephrotoxicity and that this class of antibiotics may therefore be considered as potential candidates in urinary tract infections in children. Nevertheless adequate pharmacokinetic investigations and further studies on long-term monitoring for potential toxicity need to be conducted in pediatric populations.

Fluoroquinolone-induced renal failure

Fluoroquinolones are generally well tolerated, clinically useful antimicrobials. This paper highlights rare, but potentially serious, adverse effects involving the kidney. Other antimicrobials have long been known to cause various forms of nephrotoxicity occurring as allergic interstitial nephritis, granulomatous interstitial nephritis, necrotising vasculitis, allergic tubular nephritis or a tubular necrosis. A Medline search (1985 to May 1999) of ciprofloxacin, norfloxacin, levofloxacin, ofloxacin, trovafloxacin, enoxacin, sparfloxacin, grepafloxacin, gatifloxacin, clinafloxacin and moxifloxacin was conducted to ascertain the incidence and features of fluoroquinolone nephrotoxicity. Unfortunately, the data primarily consist of case reports and temporally related events. The incidence of these adverse effects is hard to estimate, and the cause may be multifactorial. While the use of ciprofloxacin appears to increase the risk, this may be due to its longer and more widespread use when compared with the newer agents.

Drug-induced acute interstitial nephritis in renal allografts: histopathologic features and clinical course in six patients

Drug-induced acute interstitial nephritis is a common cause of dysfunction in native kidneys, but is rarely reported in renal allografts. This report describes six renal transplant recipients with acute renal allograft dysfunction or delayed allograft function in whom a renal transplant biopsy showed histopathologic features of drug-induced interstitial nephritis with no diagnostic evidence of acute rejection, cyclosporine or tacrolimus nephrotoxicity, or other lesion that could account for the graft dysfunction. In five of the six patients, interstitial nephritis occurred within 4 weeks of transplantation. All the patients were receiving trimethaprim-sulfamethoxazole and/or other drugs associated with interstitial nephritis. After discontinuation of these drugs and short-term corticosteroid treatment, all patients showed improvement in renal function, although the time course of this improvement varied considerably, with three patients showing a return to baseline serum creatinine level within 2 weeks and two patients showing a gradual improvement over 8 weeks. Four of the five patients followed up for more than 1 year (range, 14 to 33 months) after the episode of interstitial nephritis had good allograft function (serum creatinine level </= 1.6 mg/dL) at most recent follow-up, with one patient who had graft loss because of severe rejection 7.5 months after the development of interstitial nephritis. These findings suggest drug-induced interstitial nephritis may be an infrequent cause of graft dysfunction in kidney transplant recipients. Drug-induced interstitial nephritis is a reversible lesion that should be considered in the differential diagnosis of acute renal allograft dysfunction.

Acute tubulointerstitial nephritis associated with piperacillin therapy in a boy with glomerulonephritis

An 11-year-old boy with glomerulonephritis developed acute renal failure 4 days after beginning piperacillin (PIPC) treatment. Renal biopsy revealed acute tubulointerstitial nephritis (ATIN) with marked eosinophils. A lymphocyte stimulation test (LST) for PIPC demonstrated an extremely high LST index of 626%. The serum levels of immunoglobulin E and eosinophil cationic protein also showed a significant increase at 9021 IU/mL and greater than 150 micrograms/L, respectively. These observations suggest that a hypersensitivity reaction might play a role in the pathogenesis of ATIN. This is the first report to describe PIPC-induced ATIN in a child.

Renal vasculitis associated with ciprofloxacin

We report two patients treated with ciprofloxacin who presented with acute renal failure. On renal biopsy, a necrotizing vasculitis was identified in addition to acute interstitial nephritis. Improvement in renal function resulted with the discontinuation of the antibiotic and the institution of immunosuppressive therapy.