Relationship between bone marrow iron load and liver iron concentration in dialysis-associated haemosiderosis.

BACKGROUND: Iron overload due to the excessive use of parenteral iron in haemodialysis is now an increasingly recognised clinical issue. Before erythropoiesis-stimulating agents (ESA) were introduced, a specific feature of patients treated by dialysis and having iron overload was that iron levels in the bone marrow were paradoxically low in most of them, despite severe hepatosplenic siderosis. Whether or not this paradox persists in the actual ESA era was unknown until recently, when an autopsy study in 21 patients treated by haemodialysis revealed similarities between liver and bone marrow iron content. The aim of this study was to further explore these recent findings in a cohort of alive patients on dialysis and to analyse the determinants of iron bone marrow. METHODS: Liver iron concentration (LIC) and vertebral T2∗ (a surrogate marker of bone marrow iron) were analysed retrospectively in 152 alive patients on dialysis (38.8% female) of whom 47.4% had iron overload by quantitative magnetic resonance imaging (MRI). FINDINGS: Vertebral T2∗ differed significantly between patients classified according to liver iron content at MRI: those with mild or moderate and severe liver iron overload had increased vertebral iron content at R2∗ relaxometry MRI (mild: vertebral T2∗ = 9.9 ms (4-24.8); moderate and severe: vertebral T2∗ = 8.5 ms (4.9-22.8)) when compared to patients with normal LIC (vertebral T2∗ = 13.2 ms (6.6-30.5) (p < 0.0001 Kruskal-Wallis test)). INTERPRETATION: The paradoxical discrepancy between bone marrow and liver iron-storage compartments observed in the pre-ESA era has disappeared today, as shown by a recent autopsy study and the present study in a cohort of alive patients treated by dialysis. FUNDING: None.

Cerebellar Superficial Siderosis in Cerebral Amyloid Angiopathy on 1.5T T2*-Weighted Imaging.

BACKGROUND: Cerebellar superficial siderosis (SS) has been recently reported to be present in about 10% of both hereditary and sporadic cerebral amyloid angiopathy (CAA) on 3T MRI using primarily susceptibility-weighted imaging. OBJECTIVES: Our aim was to assess cerebellar SS in sporadic CAA patients using 1.5T T2*-weighted MRI and to evaluate possible underlying mechanisms. METHOD: We retrospectively screened MRI scans of sporadic probable CAA patients initially presenting with intracerebral hemorrhage-, acute subarachnoid hemorrhage- or cortical SS-related symptoms between September 2009 and January 2022 registered in our stroke database. Patients with familial CAA were excluded. On 1.5T T2*-weighted MRI, cerebellar SS (including kappa statistics for interobserver agreement) was assessed together with typical CAA hemorrhagic features and with the presence of supratentorial macrobleed and cortical SS adjacent to the tentorium cerebelli (TC) and TC hemosiderosis. RESULTS: We screened 151 patients and finally included 111 CAA patients (median age 77) with cerebellar SS observed in 6 (5%) patients. Cerebellar SS presence was associated with a higher number of supratentorial macrobleeds (median n = 3 vs. n = 1, p = 0.0012), presence of supratentorial macrobleed adjacent to the TC (p = 0.002), and TC hemosiderosis (p = 0.005). CONCLUSIONS: Cerebellar SS in CAA patients can be identified on 1.5T T2*-weighted imaging. Associated MRI characteristics suggest contamination from supratentorial macrobleeds.

Hemosiderosis in chronic dialysis patients: Monitoring the response to deferasirox by quantitative hepatic magnetic resonance imaging.

INTRODUCTION: Hemosiderosis of chronic dialysis has always been a frequent phenomenon in dialysis; formerly related to blood transfusions before the advent of Erythropoiesis Stimulating Agents (ESA), it is currently in connection with the use of massive doses of injectable iron, to ensure the full therapeutic efficacy of ESA. Few studies have looked at the therapeutic aspect of iron chelators in the dialysis population. METHODS: We followed 31 dialysis patients treated for secondary hemosiderosis with deferasirox (DFX) at the dose 10 mg/kg/day, by hepatic MRI from September 2017 to September 2021, in order to evaluate the efficacy of iron chelators on the reduction of liver iron concentration (LIC). The diagnosis of hemosiderosis was carried for a value of the LIC > 50 µmol/g of dry liver. RESULTS: Chelation resulted in a significant reduction in liver iron burden as measured by liver MRI: (201.4 ± 179.9 vs. 122.6 ± 154.3 µmol/g liver) (p = 0.000) and in mean ferritin level: (2058.8 ± 2004.9 vs. 644.2 ± 456.6 ng/mL) (p = 0.002). A gain of 1.1 g/dL in mean hemoglobin level: (10.5 ± 1.6 vs. 11.6 ± 2.0 g/dL) (p = 0.006). A significant increase in mean albumin level: (43 ± 5.5 to 46.2 ± 6.1 g/L) (p = 0.04). The therapeutic response was clearly influenced by the cause of overload, longer in polytransfused patients (p = 0.023) and the degree of overload assessed by MRI (p = 0.003) and ferritin level (p = 0.04). CONCLUSION: DFX, prescribed at a dose of 10 mg/kg/day, resulted in a significant reduction in hepatic iron burden as measured by liver MRI and ferritin. The therapeutic response was clearly influenced by blood transfusions and the degree of iron overload.

Ferritin thresholds for cardiac and liver hemosiderosis in ß-thalassemia patients: a diagnostic accuracy study.

Ferritin is frequently used to screen some dire consequences of iron overload in ß-thalassemia patients. The study aimed to define the best cutoff point of ferritin to screen for cardiac and liver hemosiderosis in these cases. This was a registry-based study on ß-thalassemia patients living throughout Mazandaran province, Iran (n = 1959). In this diagnostic research, the index test was ferritin levels measured by a chemiluminescent immunoassay. As a reference test, T2*-weighted magnetic resonance imaging (T2*-weighted MRI) was applied to determine cardiac and liver hemosiderosis. A cutoff point of 2027 ng/mL for ferritin showed a sensitivity of 50%, specificity 77.4%, PPV 42.1%, and NPV 82.5% for cardiac hemosiderosis (area under curve [AUC] 0.66, 95% CI 0.60-0.71, adjusted odds ratio [OR] 2.05, 95% CI 1.05-4.01). At an optimum cutoff point of 1090 ng/mL, sensitivity 66.7%, specificity 68%, PPV 82.9%, and NPV 46.8% for liver hemosiderosis were estimated (AUC 0.68, 95% CI 0.63-0.73, adjusted OR 3.93, 95% CI 2.02-7.64. The likelihood of cardiac hemosiderosis serum ferritin levels below 2027 ng/mL is 17.5%. Moreover, 82.9% of ß-thalassemia patients with serum ferritin levels above 1090 ng/mL may suffer from liver hemosiderosis, regardless of the grades.

A challenging case of an adolescent and young adult patient with high-risk acute lymphoblastic leukemia: the need for a multidisciplinary approach: a case report.

BACKGROUND: Adolescents and young adults diagnosed with acute lymphoblastic leukemia are treated according to pediatric-based regimens to achieve better results. However, implementation of intensive chemotherapy protocols in this age group is associated with increased treatment-related toxicities, affecting almost every organ and system. In this case, the focus of our interest was on rather rare entities: steroid-induced psychosis that seldom develops in children and adolescents, and choroid plexus hemosiderosis, infrequently identified as a first sign of iron overload. CASE PRESENTATION: The aim of this paper is to present a challenging case of a 15-year-old Caucasian male patient treated for high-risk acute lymphoblastic leukemia and who experienced various adverse incidents during intensive chemotherapy, thus necessitating a high-quality multidisciplinary approach. Slow minimal residual disease clearance was an additional concerning issue. Induction and re-induction were complicated by steroid-induced hyperglycemia that required multiple-week insulin. During consolidation, acute kidney injury on the basis of chronic kidney disease was verified, demanding subsequent drug dose modifications. By the end of re-induction, after dexamethasone cessation, infrequent steroid-induced psychosis, presented as incoherent speech, aggressive behavior, and mood swings, required intensive psychiatric support. Neurological evaluation of seizures revealed uncommon choroid plexus hemosiderosis by brain magnetic resonance imaging, warranting appropriate selection of iron chelation therapy in the context of preexisting nephropathy. Ultimately, iron deposits of moderate intensity were verified by liver magnetic resonance imaging, while heart tissue remained intact. The early diagnosis and adequate treatment of aforementioned difficult toxicities resulted in complete recovery of the patient. CONCLUSIONS: Treating adolescents with high-risk acute leukemia and multiple therapy-related morbidities remains a challenge, even in the era of extensive and effective supportive therapy. Superior survival rates might be achieved by prompt recognition of both frequent and rarely encountered adverse episodes, as well as well-timed and appropriate management by a well-coordinated multidisciplinary team.

Cerebellar Superficial Siderosis in Cerebral Amyloid Angiopathy.

BACKGROUND AND PURPOSE: Although evidence accumulates that the cerebellum is involved in cerebral amyloid angiopathy (CAA), cerebellar superficial siderosis is not considered to be a disease marker. The objective of this study is to investigate cerebellar superficial siderosis frequency and its relation to hemorrhagic magnetic resonance imaging markers in patients with sporadic and Dutch-type hereditary CAA and patients with deep perforating arteriopathy-related intracerebral hemorrhage. METHODS: We recruited patients from 3 prospective 3 Tesla magnetic resonance imaging studies and scored siderosis and hemorrhages. Cerebellar siderosis was identified as hypointense linear signal loss (black) on susceptibility-weighted or T2*-weighted magnetic resonance imaging which follows at least one folia of the cerebellar cortex (including the vermis). RESULTS: We included 50 subjects with Dutch-type hereditary CAA, (mean age 50 years), 45 with sporadic CAA (mean age 72 years), and 43 patients with deep perforating arteriopathy-related intracerebral hemorrhage (mean age 54 years). Cerebellar superficial siderosis was present in 5 out of 50 (10% [95% CI, 2-18]) patients with Dutch-type hereditary CAA, 4/45 (9% [95% CI, 1-17]) patients with sporadic CAA, and 0 out of 43 (0% [95% CI, 0-8]) patients with deep perforating arteriopathy-related intracerebral hemorrhage. Patients with cerebellar superficial siderosis had more supratentorial lobar (median number 9 versus 2, relative risk, 2.9 [95% CI, 2.5-3.4]) and superficial cerebellar macrobleeds (median number 2 versus 0, relative risk, 20.3 [95% CI, 8.6-47.6]) compared with patients without the marker. The frequency of cortical superficial siderosis and superficial cerebellar microbleeds was comparable. CONCLUSIONS: We conclude that cerebellar superficial siderosis might be a novel marker for CAA.

Lung transplant to manage end-stage lung disease due to idiopathic pulmonary hemosiderosis: A review of the literature.

Idiopathic pulmonary hemosiderosis (IPH) is a rare immunological disease with a genetic predisposition. It is characterized by recurrent episodes of diffuse alveolar hemorrhage (DAH). Timely use of immunosuppressive medications has significantly improved overall outcomes, including mortality. Still, uncontrolled and frequent episodes of DAH can eventually cause pulmonary fibrosis, leading to end-stage lung disease (ESLD). The objective of the present project was to scrutinize the literature and summarize the demographic, clinical, radiological, and histopathological features, as well as the overall outcomes, in this patient population following lung transplant. The Medline database was searched using the PubMed platform. Articles published in English between 1960 and 2020 were included in the search. Different search terms were used to identify all patients who underwent lung transplantation to manage ESLD due to IPH. Only four cases of lung transplantation have been reported in the literature in patients with IPH. All but one of these underwent deceased donor lung transplant; recurrence was reported in two of these patients and suspected in the third. One patient received living donor lung transplant and had no recurrence during a five-year follow-up. Patients with IPH should not be excluded from lung transplantation because the disease may not recur in all patients, and even when it does recur it can be promptly treated by increasing immunosuppression.

High-Grade Fetal Vascular Malperfusion Is Associated With Diffuse Chorionic Hemosiderosis.

INTRODUCTION: Diffuse chorionic hemosiderosis (DCH) is an abnormality of the placental membranes characterized by the deposition of iron pigment. It is usually secondary to recurrent venous bleeding in early pregnancy. In many papers, it is associated with pre-term delivery. Fetal vascular malperfusion (FVM) is an abnormality of the feto-placental circulation that may be seen at any stage of gestation, but most often in the third trimester. It may be graded as low grade (LGFVM) or high grade (HGFVM). No link has been identified in the placental literature between DCH and FVM, but we have noted the 2 co-existing in placentas submitted for analysis. This study explored a possible association of these 2 entities. METHODS: Laboratory records were searched for singleton cases coded as DCH based on diagnosis on H&E stain over a 6-year period. Of 4478 placentas reported, 66 cases were coded as DCH (1.5%). These were classified as showing HGFVM, LGFVM, or no FVM. Controls (n = 132) were gestational age-matched cases without DCH. Cord length, coiling, insertion, or other abnormalities were noted. Membranes were classified as normal or circumvallate. Results were analyzed using Graphpad. RESULTS: Gestation ranged between 16 and 41 weeks gestation. 14/66 (21%) cases of DCH showed HGFVM and 2/66 (3%) showed LGFVM. 16/132 (12%) controls showed HGFVM and 21/132 (15.9%) had LGFVM. Where FVM is present, high-grade FVM is significantly associated with DCH versus controls (P < .0031 Fischer's Test). DISCUSSION: HGFVM occurs significantly more often in placentas with DCH than in controls. Both FVM and DCH are associated with adverse perinatal outcomes, and a possible relationship between the 2 remains to be clarified.

Renal hemosiderosis presenting with acute kidney Injury and macroscopic hematuria in Immunoglobulin A nephropathy: a case report.

BACKGROUND: Macroscopic hematuria-associated acute kidney injury (AKI) is a well-known complication of immunoglobulin A (IgA) nephropathy. In such cases, intratubular obstruction by red blood cell (RBC) casts and acute tubular necrosis are mainly observed pathologically. Herein, we report the case of a patient with IgA nephropathy presenting with AKI following an episode of macrohematuria. The patient presented with severe renal tubular hemosiderosis and acute tubular necrosis and without any obvious obstructive RBC casts. CASE PRESENTATION: A 68-year-old woman, who was diagnosed with IgA nephropathy on renal biopsy 6 years ago, was admitted to our hospital after an episode of macroscopic glomerular hematuria and AKI following upper respiratory tract infection. Renal biopsy showed mesangial proliferation of the glomeruli, including crescent formation in 17 % of the glomeruli, and acute tubular necrosis without obvious hemorrhage or obstructive RBC casts. The application of Perls' Prussian blue stain showed hemosiderin deposition in the renal proximal tubular cells. Immunofluorescence showed granular mesangial deposits of IgA and C3. Based on these findings, she was diagnosed with acute tubular necrosis with a concurrent IgA nephropathy flare-up. Moreover, direct tubular injury by heme and iron was considered to be the cause of AKI. She was treated with intravenous pulse methylprednisolone followed by oral prednisolone. Thereafter, the gross hematuria gradually faded, and her serum creatinine levels decreased. CONCLUSIONS: IgA nephropathy presenting with acute kidney injury accompanied by macrohematuria may cause renal hemosiderosis and acute tubular necrosis without obstructive RBC casts. Hemosiderosis may be a useful indicator for determining the pathophysiology of macroscopic hematuria-associated AKI. However, renal hemosiderosis may remain undiagnosed. Thus, Perls' Prussian blue iron staining should be more widely used in patients presenting with hematuria.

In vivo calibration of the T2* cardiovascular magnetic resonance method at 1.5 T for estimation of cardiac iron in a minipig model of transfusional iron overload.

BACKGROUND: Non-invasive estimation of the cardiac iron concentration (CIC) by T2* cardiovascular magnetic resonance (CMR) has been validated repeatedly and is in widespread clinical use. However, calibration data are limited, and mostly from post-mortem studies. In the present study, we performed an in vivo calibration in a dextran-iron loaded minipig model. METHODS: R2* (= 1/T2*) was assessed in vivo by 1.5 T CMR in the cardiac septum. Chemical CIC was assessed by inductively coupled plasma-optical emission spectroscopy in endomyocardial catheter biopsies (EMBs) from cardiac septum taken during follow up of 11 minipigs on dextran-iron loading, and also in full-wall biopsies from cardiac septum, taken post-mortem in another 16  minipigs, after completed iron loading. RESULTS: A strong correlation could be demonstrated between chemical CIC in 55 EMBs and parallel cardiac T2* (Spearman rank correlation coefficient 0.72, P < 0.001). Regression analysis led to [CIC] = (R2* - 17.16)/41.12 for the calibration equation with CIC in mg/g dry weight and R2* in Hz. An even stronger correlation was found, when chemical CIC was measured by full-wall biopsies from cardiac septum, taken immediately after euthanasia, in connection with the last CMR session after finished iron loading (Spearman rank correlation coefficient 0.95 (P < 0.001). Regression analysis led to the calibration equation [CIC] = (R2* - 17.2)/31.8. CONCLUSIONS: Calibration of cardiac T2* by EMBs is possible in the minipig model but is less accurate than by full-wall biopsies. Likely explanations are sampling error, variable content of non-iron containing tissue and smaller biopsies, when using catheter biopsies. The results further validate the CMR T2* technique for estimation of cardiac iron in conditions with iron overload and add to the limited calibration data published earlier.

Idiopathic pulmonary hemosiderosis: A state of the art review.

Idiopathic pulmonary hemosiderosis (IPH) is an uncommon cause of diffuse alveolar hemorrhage (DAH). Patients with IPH usually present with hemoptysis, and the diagnosis is often delayed by years. Patients often present with intermittent episodes of hemoptysis interspersed between periods of relative normalcy. However, massive hemorrhage resulting in acute respiratory failure and non-remitting hemoptysis have also been described. The classic triad includes hemoptysis, radiologic lung infiltrate, and iron deficiency anemia. Several hypotheses regarding the pathogenesis of IPH have been proposed. These risk factors include an autoimmune, allergic or genetic predisposition, and possible environmental exposure. Since IPH appears to be responsive to corticosteroids, the autoimmune hypothesis is considered to play a crucial role. A diagnosis of IPH requires exclusion of other etiologies of DAH, including infection, medications, toxic inhalation, vasculitis, and anti-glomerular basement membrane disease, among others. Histologically, IPH is characterized by the presence of hemosiderin-laden macrophages in the alveolar space without any evidence of vasculitis or immunocomplex deposition. Corticosteroid therapy represents the primary modality of treatment. Other immunosuppressive medications have also been used with varying success, especially in the setting of steroid-refractory disease. The prognosis of IPH in adults is somewhat better compared to the pediatric population. The severity of the initial presentation does not predict future outcomes. Which risk factors and patient characteristics are associated with a poor outcome are also unknown. More research is necessary to elucidate the pathophysiology and appropriate treatment.

Cobalamin C deficiency presenting with diffuse alveolar hemorrhage and pulmonary microangiopathy.

OBJECTIVE: Combined methylmalonic acidemia and homocysteinemia is a genetically heterogeneous disorder of cobalamin (cbl; vitamin B12) metabolism, which consists of five subtypes including cblC, cblD, cblF, cblJ, and cblX deficiencies. The purpose of this study is to summarize new clinical features mainly diffuse alveolar hemorrhage (DAH) in cblC deficiency. METHODS: We made a retrospective analysis of four pediatric patients diagnosed with DAH and pulmonary microangiopathy due to cblC deficiency between January 2017 and December 2018 in Beijing Children's Hospital. RESULTS: This study describes four patients with their ages ranging from 4 years 2 months to 7 years 6 months with cblC deficiency who developed late-onset diffuse lung disease (DLD). Of these, the first three patients presented predominantly with DAH, and the last patient with pulmonary microangiopathy confirmed by thoracoscopic lung biopsy. All patients were accompanied by pulmonary arterial hypertension (PAH), two accompanied by respiratory failure, and two accompanied by moderate megaloblastic anemia. Diffuse ground-glass opacification and poorly defined ground-glass centrilobular nodules were seen on high-resolution computed tomography in one patient and three patients, respectively. All patients were suspected of having idiopathic pulmonary hemosiderosis or interstitial lung disease at other hospitals. All of them received treatment with corticosteroid before admission, but the symptoms did not improve. Moreover, all patients carried compound heterozygous mutations (c.80A>G, c.609G>A) in MMACHC and improved significantly after being treated for cblC deficiency and PAH. CONCLUSIONS: CblC deficiency should be considered in the differential diagnosis of DAH especially with PAH, and pulmonary microangiopathy be the main reason of DLD in these patients.

Cortical superficial siderosis progression in cerebral amyloid angiopathy: Prospective MRI study.

OBJECTIVE: To investigate the prevalence, predictors, and clinical relevance of cortical superficial siderosis (cSS) progression in cerebral amyloid angiopathy (CAA). METHODS: Consecutive patients with symptomatic CAA meeting Boston criteria in a prospective cohort underwent baseline and follow-up MRI within 1 year. cSS progression was evaluated on an ordinal scale and categorized into mild (score 1-2 = cSS extension within an already present cSS focus or appearance of 1 new cSS focus) and severe progression (score 3-4 = appearance of ≥2 new cSS foci). Binominal and ordinal multivariable logistic regression were used to determine cSS progression predictors. We investigated future lobar intracerebral hemorrhage (ICH) risk in survival analysis models. RESULTS: We included 79 patients with CAA (mean age, 69.2 years), 56 (71%) with lobar ICH at baseline. cSS progression was detected in 23 (29%) patients: 15 (19%) patients had mild and 8 (10%) severe progression. In binominal multivariable logistic regression, ICH presence (odds ratio [OR], 7.54; 95% confidence interval [CI], 1.75-53.52; p = 0.016) and baseline cSS (OR, 10.41; 95% CI, 2.84-52.83; p = 0.001) were independent predictors of cSS progression. In similar models, presence of disseminated (but not focal) cSS at baseline (OR, 5.58; 95% CI, 1.81-19.41; p = 0.004) was an independent predictor of cSS progression. Results were similar in ordinal multivariable logistic regression models. In multivariable Cox regression analysis, severe cSS progression was independently associated with increased future ICH risk (HR, 5.90; 95% CI, 1.30-26.68; p = 0.021). CONCLUSIONS: cSS evolution on MRI is common in patients with symptomatic CAA and might be a potential biomarker for assessing disease severity and future ICH risk. External validation of these findings is warranted.

Superficial Siderosis Associated with Long-Term Recurrence of Pilocytic Astrocytoma in an Elderly Person.

BACKGROUND: Superficial siderosis is an irreversible disease in the central nervous system caused by the deposition of hemosiderin in the subpial tissue due to persistent bleeding in the subarachnoid space. The main symptoms include sensorineural hearing loss, cerebellar ataxia, and pyramidal tract disorder. Superficial siderosis is mainly idiopathic, but bleeding factors such as tumors or history of surgery often play an important role in its pathogenesis. CASE DESCRIPTION: A 66-year-old man with a history of surgery for a cerebellar tumor 37 years ago complained of hearing loss. Magnetic resonance imaging showed recurrence of the tumor on T2-weighted images and hypointense areas along the cerebellar sulci on T2∗-weighted images. During the operation, microscopic bleeding was observed on the surface of the tumor. The pathologic diagnosis was pilocytic astrocytoma. A biopsy obtained during the first surgery revealed almost the same pathologic findings as those from a biopsy obtained during the second surgery, but the first specimen showed no hemosiderin deposition or active bleeding, which the second specimen did show. CONCLUSIONS: Recurrent pilocytic astrocytoma with intratumoral hemorrhage was the suspected cause for superficial siderosis. The source of chronic bleeding was identified with intraoperative and pathologic findings. We describe the first report of superficial siderosis associated with a pilocytic astrocytoma that recurred 37 years after an initial tumor was excised.

Renal hemosiderosis secondary to intravascular hemolysis after mitral valve repair: A case report.

RATIONALE: Renal hemosiderosis is a disease in which hemosiderin deposits in the renal cortex as a form of iron overload. However, cases of renal hemosiderosis due to intravascular hemolysis following mitral valve repair have been rarely reported. PATIENT CONCERNS: We present the case of a 62-year-old woman who developed asymptomatic urinary abnormalities including microscopic hematuria and proteinuria due to renal hemosiderosis following a mitral valve repair surgery performed two years earlier. DIAGNOSES: A percutaneous renal biopsy showed no specific glomerular abnormality, tubular atrophy, or interstitial fibrosis but extensive deposition of hemosiderin in the proximal tubule. The patient was diagnosed with renal hemosiderosis and chronic intravascular hemolysis following mitral valve repair. INTERVENTIONS: Our patient refused a mitral valve repeat surgery and hence was treated with oral iron preparations, N-acetylcysteine, and a ß-receptor blocker. OUTCOMES: Moderate mitral regurgitation with the regurgitant blood striking against the annuloplasty ring was confirmed on follow-up echocardiography. After the 24-month follow-up period, hemolytic anemia persisted, but there was no significant decline of renal function. LESSONS: For cases of chronic intravascular hemolysis accompanied with asymptomatic urinary abnormalities, a renal biopsy is required to exclude underlying kidney pathology and predict potential renal insufficiency.