Hemorrhagic cystitis after allogeneic bone marrow transplantation in children: clinical characteristics and outcome

Risk factors for hemorrhagic cystitis in children undergoing hematopoietic stem cell transplantation: a systematic review and meta-analysis

BACKGROUND

The risk factors for hemorrhagic cystitis (HC) in children undergoing hematopoietic stem cell transplantation (HSCT) are unclear. Therefore, we conducted this systematic review and meta-analysis to investigate the risk factors for HC in children undergoing HSCT.

METHODS

We performed this meta-analysis by retrieving studies from PubMed, EMBASE, and the Cochrane Library up to October 10, 2023, and analyzing those that met the inclusion criteria. I2 statistics were used to evaluate heterogeneity.

RESULTS

Twelve studies, including 2,764 patients, were analyzed. Male sex (odds ratio [OR] = 1.52; 95% confidence interval [CI], 1.16-2.00; p = 0.003, I2 = 0%), allogeneic donor (OR = 5.28; 95% CI, 2.60-10.74; p < 0.00001, I2 = 0%), human leukocyte antigen (HLA) mismatched donor (OR = 1.86; 95% CI, 1.00-3.44; p = 0.05, I2 = 31%), unrelated donor (OR = 1.58; 95% CI, 1.10-2.28; p = 0.01, I2 = 1%), myeloablative conditioning (MAC) (OR = 3.17; 95% CI, 1.26-7.97; p = 0.01, I2 = 0%), busulfan (OR = 2.18; 95% CI, 1.33-3.58; p = 0.002, I2 = 0%) or anti-thymoglobulin (OR = 1.65; 95% CI, 1.07-2.54; p = 0.02, I2 = 16%) use, and cytomegalovirus (CMV) reactivation (OR = 2.64; 95% CI, 1.44-4.82; p = 0.002, I2 = 0%) were risk factors for HC in children undergoing HSCT.

CONCLUSIONS

Male sex, allogeneic donor, HLA-mismatched, unrelated donor, MAC, use of busulfan or anti-thymoglobulin, and CMV reactivation are risk factors for HC in children undergoing HSCT.

Analysis of early clinical signs and risk factors for severe hemorrhagic cystitis after stem cell transplantation in children

INTRODUCTION

To analyze the characteristics of early clinical symptoms of hemorrhagic cystitis (HC) after hematopoietic stem cell transplantation (HSCT) and the risk factors of severe HC.

METHODS

We retrospectively analyzed 77 children with post-HSCT HC treated at our hospital between June 2013 and June 2021. Clinical characteristics were collected and catalogued.

RESULTS

Among the children with urinary tract irritation symptoms (UTIS) as the first symptom, symptoms appeared earlier than hematuria symptoms (28 day vs. 31 day, p = 0.027), and the time progressing to severe HC was significantly longer in these children (12 day vs. 7 day, p = 0.038), but there was no significant difference in the number of participants (57.8% vs. 59.4%, p = 0.889). BK polyomavirus (BKV) infection was an independent risk factor (hazard ratio [HR] = 2.782, p = 0.035) for severe HC, which was also positively associated with multi-viral infection (HR = 2.215, p = 0.020).

CONCLUSIONS

In HC children, when the first urinary tract symptom was UTIS, it appeared earlier than hematuria, and the time of progression to severe HC was significantly longer, suggesting that we still need more aggressive treatment for these children to prevent the worsening of symptoms. The severity of HC was positively correlated with BKV infection and multiple infections.

[Haemorrhagic cystitis following hematopoietic stem cell transplantation: Prophylaxis, diagnosis, and treatment. Guidelines from the SFGM-TC]

Hemorrhagic cystitis (HC) is a common complication after allogeneic hematopoietic cell transplantation (allo-HCT). Its manifestations range from microscopic hematuria without urinary symptoms to extensive and prolonged macroscopic hemorrhage requiring invasive interventions that can often prolong the duration of hospitalization and result in significant morbidity. The early onset of HC is related to allo-HCT conditioning regimen, whereas the late onset form is secondary to viral infection, most commonly due to BK virus. In the framework of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) practice harmonization workshops held in Lille in September 2021, the prophylaxis, the diagnostic approach and the treatments of HC following allografting were reviewed after analysis of published studies.

Incidence of hemorrhagic cystitis following unmanipulated peripheral blood stem cell transplantation in acute Leukemia: A retrospective single-center risk factor analysis

BACKGROUND

Hemorrhagic cystitis (HC) is an important adverse event experienced after hematopoietic stem cell transplantation (HSCT). Severe HC could lead to significant morbidity, prolonged hospitalization with increased health-care costs, and may cause considerable mortality.

OBJECTIVES

In order to investigate the influence of different contributing factors other than BK viruria on HC occurrence in a homogenous population, we retrospectively analyzed the potential risk factors.

STUDY DESIGN

We conducted a retrospective study among 200 patients (median age 12.4 years, IQR: 7.9-16.1) with acute leukemia who received peripheral blood allogenic HSCT after radiation-free myeloablative conditioning regimen, in pediatric cell therapy department of Research Institute for Oncology, Hematology and Cell Therapy (RIOHCT), Tehran, Iran, between December 2014 and December 2021. Associations between risk factors and outcomes were examined by univariable and multivariable logistic regression models.

RESULTS

A total of 46 patients (23%) had developed HC during the study period. The median onset of HC was 29 (IQR: 24-37) days post-transplant, and it persisted for a median of 33 (7-270) days. The incidence of HC in our patients was estimated to be 3 in 1000 cases (95% CI: 2-4). The results of multivariable logistic model shows that the chance of HC in T-cell acute lymphoblastic leukemia (ALL) compared to B-cell All is nearly five times more (OR = 4.88; 95%CI: (1.51-15.78), P = 0.008). The incidence of HC in patients who underwent HSCT from haploidentical donors was significantly higher than full matched donors (P < 0.001). Undergoing transplant from a matched unrelated and haploidentical donor both augment the chance of HC in about six times more than matched related donors (OR = 6.36; 95%CI: (1.58-25.49), P = 0.009 and OR = 5.7; 95%CI: (1.83-17.75), P = 0.003, respectively). In patients who developed HC compared to non-HC group, overall survival was much worse (P < 0.001).

DISCUSSION

Most studies have failed to demonstrate any relationship between late-onset HC and the dose of cyclophosphamide. In our study, although the dose of cyclophosphamide was similar in HSCT from MRD and MUD, the hazard of HC incidence was significantly higher in the latter group. This could be accredited to ATG, as in patients in the MRD group who had not received any ATG, the incidence of HC was much lower than the patients who had underwent HSCT from MUD or haploidentical donor group.

CONCLUSIONS

Patients with T-cell ALL and those who under haploidentical HSCT had the highest incidence of HC.

Prognostic Value of Thrombocytopenia in Myelodysplastic Syndromes After Hematopoietic Stem Cell Transplantation

Prolonged isolated thrombocytopenia (PT) is a common complication affecting the outcome of stem cell transplantation. In this study, we undertook a real-world study of 303 myelodysplastic syndrome (MDS) patients who received allogeneic hematopoietic stem cell transplantation (HSCT) between December 2007 and June 2018. 28.4% of MDS patients suffered from PT after HSCT. Survival analysis indicated that PT was associated with worse overall survival (OS) in MDS patients. The 2-year and 5-year OS in MDS patients with PT after HSCT were 49% and 47%, significantly worse than that of 68% and 60% in patients without PT (P=0.005). For RFS, patients with PT did not have an increased risk of disease relapse (P=0.964). After multivariate adjustment, PT was proved to be the independent risk factor associated with the worse OS (HR 1.49, 95% CI 1.00-2.21, P =0.048). We further analyzed risk factors associated with the occurrence of PT in MDS patients. Multiple logistic regression identified grade II-IV aGVHD, extensive chronic GVHD, hemorrhagic cystitis, and CMV activation as significant risk factors for developing PT. Among these variables, the Odds Ratio (OR) of grade II-IV aGVHD was the highest (P =0.001, OR: 2.65, 95% CI: 1.51-4.64). These data indicated the prognostic value of PT in MDS after HSCT. The identification of risk factors for PT may help improve patient management and lead to the design of effective treatment strategies.

Prospective analysis of BKV hemorrhagic cystitis in children and adolescents undergoing hematopoietic cell transplantation

BK virus is one of the most common causes of hemorrhagic cystitis (HC) in children undergoing hematopoietic cell transplantation (HCT). Viruses can be found in urine and serum samples of immunocompromised patients. Malignant diseases, age, cell source, day of granulocyte reconstitution, conditioning regimen, or use of total body irradiation may play an important role in BKV epidemiology, development of hemorrhagic cystitis course, and outcome. The aim of this study was to evaluate the incidence, clinical course, and risk factors for BKV-HC in children undergoing HCT. A total number of 133 patients who were prospectively tested for BKV colonization/infection were enrolled into this multicenter analysis. Episodes of BKV-HC occurred in 36/133 (27%) enrolled subjects. In a univariate analysis for BKV-HC incidence, the following factors were significant: age >5 years, peripheral blood transplantation, matched unrelated donor (MUD) transplantation, busulfan-cyclophosphamide-melphalan conditioning regimen, and acute myeloblastic leukemia (AML) diagnosis. Presence of acute graft-versus-host disease (aGVHD) in liver and gut GVHD was a significant risk factor of BKV-HC. No BKV-attributed deaths were reported. In multivariate analysis, the incidence of HC was significantly higher in patients with AML, age >5 years, MUD transplants, and children with GVHD. HC is a frequent complication after HCT among children causes prolonged hospitalization but rarely contributes to death. We identified risk factors of BKV-HC development in children, with focus on aGVHD: we concluded that excessive immune reaction connected with GVHD and immunosuppression drugs might play a pivotal role in the development of BKV-HC.

Complications of Stem Cell Transplantation that Affect Infections in Stem Cell Transplant Recipients, with Analogies to Patients with Hematologic Malignancies

This article discusses the complications of hematopoietic stem cell transplantion (HSCT) that affect infections in HSCT recipients, with analogies to patients with hematologic malignancies. Mucositis, with mucosal barrier disruption, is common and increases the risk of gram-positive and anaerobic bacterial, and fungal infections, and can evolve to typhlitis. Engraftment syndrome; graft-versus-host disease, hepatic sinusoidal obstruction syndrome; and posterior reversible encephalopathy syndrome can affect the infectious potential either directly from organ dysfunction or indirectly from specific treatment. Pulmonary infections can predispose to life threatening complications including diffuse alveolar hemorrhage, idiopathic pulmonary syndrome, bronchiolitis obliterans syndrome, and bronchiolitis obliterans with organizing pneumonia.

High incidence of BK virus-associated hemorrhagic cystitis in children after second or third allogeneic hematopoietic stem cell transplantation

BKV-HC is a serious complication of allogeneic HSCT. To characterize the incidence, risk factors, and clinical outcomes of post-HSCT BKV-HC, we retrospectively analyzed 112 patients who underwent one or more allogeneic HSCTs at our hospital between 2001 and 2017. Twenty underwent second or third HSCT thereafter. Ten patients developed BKV-HC at a median of 30 days after HSCT. The 100-day cumulative incidences of grade 0-4 and grade 2-4 BKV-HC were 7.8% and 6.2%, respectively. HSCTs performed in 2011-2017 associated with significantly higher 100-day cumulative incidence of grade 2-4 BKV-HC (14.0%) than HSCTs performed in 2001-2010 (1.3%, P = 0.004). On multivariate analysis, second or third HSCT was the only independent significant risk factor for development of grade 2-4 BKV-HC (P = 0.015). Serial PCR monitoring of urine and blood BKV load did not predict BKV-HC. The recent increase in the incidence of BKV-HC may reflect recent innovations in transplant technologies that facilitate second or third HSCT, which are known to cause prolonged immune deficiency. If safe and effective treatment or prophylaxis becomes available, it could be used to target the high-risk patients for BKV-HC.

Thrombotic and hemorrhagic complications in children and young adult recipients of Hematopoietic Stem Cell Transplant (HSCT)

BACKGROUND

Overall incidence of hemostatic complications in pediatric recipients of Hematopoietic Stem Cell Transplant (HSCT) is scarcely studied. This retrospective review explored the incidence and underlying risk factors of bleeding and thrombotic complications in children.

PROCEDURE

Clinical characteristics, hemorrhagic events (HE), thrombotic events (TE) and follow up data were abstracted from medical records on patients aged <21 years undergoing HSCT during January 2000-June 2015.

RESULTS

From start of conditioning until last follow up, 238 pediatric patients were reviewed during this study. There were 16 symptomatic thrombotic complications in 15 patients, along with 13 major bleeding events. Incidence of HE or TE was higher in allogeneic HSCT compared to autologous HSCT (p = 0.02). Severe thrombocytopenia could not be identified as a major contributor to bleeding. All patients with HE had platelets between 20,000-50,000 × 10⁹/L, except one patient, who had platelets <20,000 × 10⁹/L. All patients with hemorrhagic cystitis (n = 7) had received cyclophosphamide (Cy). For patients with sinusoidal obstruction syndrome, conditioning included either busulfan (Bu)/Cy (n = 5), Cy with total body irradiation (n = 4), or thiotepa (n = 2). Among allogeneic HSCT recipients, 60% of HE and 92% with TE had underlying myeloid neoplasms. Graft versus Host disease contributed to both types of complications (p = 0.07), although not reaching statistical significance.

CONCLUSIONS

Allogeneic pediatric HSCT patients had higher overall risk of hemorrhagic or thrombotic complications compared to autologous recipients in this study. HSCT for myeloid malignancies was a risk factor for higher complications.

Rare Cyclophosphamide-Induced Hemorrhagic Cystitis in a Chinese Population with Rheumatic Diseases

Objective

The aim of this study was to investigate the prevalence, severity, risk factors, and treatment outcomes of cyclophosphamide (CYC)-induced hemorrhagic cystitis (HC) in patients with rheumatic diseases.

Methods

We collected the clinical data from 1284 consecutive patients admitted to The First Affiliated Hospital of Sun Yat-Sen University who were treated with CYC between 2006 and 2016, and then conducted a retrospective analysis.

Results

The mean cumulative dose of CYC was 18.3 ± 13.4 g, and the mean treatment duration of CYC was 10.0 ± 7.2 months. We identified four patients with HC, yielding a crude prevalence of 0.3%. The average time from initial primary diagnosis to HC onset was 51.6 months (33–86 months). All of the four patients with HC were exposed to a high cumulative CYC dose (>60 g). Severity was assessed as grade II in one, grade III in one and grade IV in two patients. One had resolution of hematuria after hydration, and one case resolved after combination therapy of clot removal by cystoscopy, hydration, and bladder irrigation. The other two were unresponsive to the above treatment and finally had resolution after cystectomy. The average resolution time of hematuria was 39.5 days (7–56 days). There were no deaths in our cohort.

Conclusion

CYC-induced HC was rare and highly variable in Chinese patients with rheumatic diseases. Individualized treatment should be performed according to the severity of HC for each patient. More aggressive treatment strategies might improve the outcomes of patients with high-grade HC (grades III and IV). Our findings strengthened the link between HC events and higher cumulative CYC exposure (>60 g).

BK Virus-Associated Hemorrhagic Cystitis After Allogeneic Hematopoietic Stem Cell Transplantation in the Pediatric Population

OBJECTIVE

To study the incidence, risk factors, and treatment of hemorrhagic cystitis secondary to BK-virus reactivation (HC-BKV) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the pediatric population.

METHODS

Case-control study in which all pediatric patients (0-18 years) who underwent allo-HSCT from September 2009 to January 2014 were followed.

RESULTS

Twenty-nine patients underwent an allo-HSCT. The median age was 9 years (range = 6 months to 15 years), 61% male. The primary diagnosis was acute lymphoblastic leukemia (72.4%). Six (20.7%) developed HC-BKV. In a multivariate analysis of risk factors, it was observed that the reactivation of BK virus was associated with age more than 10 years ( P = .098) and those with positive serology for Epstein-Barr virus ( P = .06). Five of the 6 patients with HC-BKV received cidofovir (CDV) at doses of 3 to 5 mg/kg/week. The treatment lasted a median of 3 cycles (range = 2-5). One of the patients (20%) developed nephrotoxicity. Of the 5 patients treated with CDV, 3 (60%) had a complete response, 1 (20%) partial response, and 1 (20%) no response.

CONCLUSION

We conclude that HC-BKV is a frequent complication after allo-HSCT. CDV therapy can be effective but controlled clinical trials are needed.

Polyomaviruses BK, JC, KI, WU, MC, and TS in children with allogeneic hematopoietic stem cell transplantation

Timely and reliable detection of viruses is of key importance in early diagnosis of infection(s) following allogeneic HSCT. Among the immunocompetent, infections with BKPyV and JCPyV are mostly subclinical, while post-HSCT, the former may cause HC and the latter PML. The epidemiology and clinical impact of the newly identified KIPyV, WUPyV, MCPyV, and TSPyV in this context remain to be defined. To assess the incidence and clinical impact of BKPyV, JCPyV, KIPyV, WUPyV, MCPyV, and TSPyV infections, we performed longitudinal molecular surveillance for DNAemias of these HPyVs among 53 pediatric HSCT recipients. Surveillance pre-HSCT and for three months post-HSCT revealed BKPyV DNAemia in 20 (38%) patients. Our data demonstrate frequent BKPyV DNAemia among pediatric patients with HSCT and the confinement of clinical symptoms to high copy numbers alone. MCPyV and JCPyV viremias occurred at low and TSPyV viremia at very low prevalences. KIPyV or WUPyV viremias were not demonstrable in this group of immunocompromised patients.

Risk Factors Associated with Severity and Outcomes in Pediatric Patients with Hemorrhagic Cystitis

PURPOSE

Hemorrhagic cystitis is a complication of treatment of pediatric cancer with considerable variation in severity and morbidity. This study presents an analysis of hemorrhagic cystitis severity and treatment outcomes in a large pediatric population.

MATERIALS AND METHODS

Patients with hemorrhagic cystitis treated at St. Jude Children's Research Hospital® were identified from 1990 to 2010. Demographic data were gathered along with information pertaining to initial primary diagnosis, hemorrhagic cystitis diagnosis and treatment, and mortality. Statistical analyses were performed to evaluate associations between risk factors and severity of hemorrhagic cystitis as well as treatment outcomes.

RESULTS

Of the 285 patients who met inclusion criteria 54% were male. Mean age was 11.41 years. Mean time from initial primary diagnosis to hemorrhagic cystitis onset was 29 months. Noninvasive treatment was performed in 246 patients (86%) and operative intervention was required in 14 (4.9%). Bivariate analysis demonstrated that pelvic radiation therapy (p = 0.0002), any radiation therapy (p = 0.005), acute lymphocytic leukemia (p = 0.01), bone marrow transplantation (p = 0.0225), cyclophosphamide exposure (p = 0.0419) and BK virus positivity (p = 0.0472) were predictors of higher grade hemorrhagic cystitis. Factors correlating with the need for invasive management on bivariate analysis included pelvic radiation therapy (p = 0.0266), bone marrow transplantation (p = 0.0007), hematological malignancy (p = 0.0066), ifosfamide exposure (p = 0.0441) and male gender (p = 0.0383). Multivariate analysis showed independent effects of pelvic radiation therapy (p = 0.001) and delayed onset of hemorrhagic cystitis (p = 0.0444).

CONCLUSIONS

Severity of hemorrhagic cystitis and failure of noninvasive management correlate with several identifiable risk factors. Prospective identification of patients with these risk factors may allow for targeted early intervention in those at highest risk.

Reactivation of polyomavirus in the genitourinary tract is significantly associated with severe GvHD and oral mucositis following allogeneic stem cell transplantation

PURPOSE

BK-virus and JC-virus are the most common polyomaviridae associated with hemorrhagic cystitis in the allogeneic transplant setting. Hemorrhagic cystitis and symptomatic viruria caused by these viruses are a major cause of morbidity in patients undergoing allogeneic stem cell transplantation.

METHODS

We performed a retrospective evaluation on a highly uniform study population of 73 patients receiving allogeneic stem cell transplantation. Patients were treated according to the FLAMSA-RIC-protocol, and were examined for the incidence of BK-/JC-viruria and late-onset BK-positive hemorrhagic cystitis within a two-year period.

RESULTS

The occurrence of BK-viruria was correlated with published risk factors (acute GvHD, oral mucositis, donor type, conditioning, age, gender). Thirty patients (41 %) were found to excrete either BK-virus (n = 17), JC-virus (n = 3) or both (n = 10), of whom 18 patients (60 %) developed higher-grade hemorrhagic cystitis as opposed to none in the virus-negative control group. Higher grade GvHD (grade B-D) was more common in patients with viruria (p = 0.013) and also more common in patients with manifest hemorrhagic cystitis (p = 0.048). Similarly, oral mucositis was associated both with viruria (p = 0.014) and hemorrhagic cystitis (p = 0.005). Manifest cystitis but not viruria was significantly associated with male gender (p = 0.016). No significant correlation was found with age, conditioning with busulfane vs total body irradiation or related vs unrelated donor.

CONCLUSIONS

Severe GvHD and oral mucositis are significantly associated with reactivation of polyomaviridae in the genitourinary-tract already at the level of asymptomatic viruria.

Correlation of the clinical parameters with sonographic findings of hemorrhagic cystitis in pediatric hematooncology patients

To find a relationship between clinical and sonographic appearance of hemorrhagic cystitis (HC) in pediatric hematooncology patients. Clinical and sonographic findings of 31 children (M:F = 18:13; mean age, 12.7 years) with HC in pediatric hematooncology patients were reviewed. For each patient, the onset of HC after transplantation, use of bladder-toxic agent, presence of BK viruria, and duration of disease were reviewed. Sonographic findings including bladder wall thickness (BWT), the type of bladder wall thickening (nodular vs. diffuse), occurrence of hydronephrosis or pyelonephritis were reviewed. We analyzed sonographic appearance and clinical manifestations of HC. HC occurred within 4 months after HSCT/BMT. 27 patients (87.0 %) were positive for BK viruria and 24 patients (77.4 %) took bladder-toxic agents. On sonography, nodular type bladder wall thickening was more frequent (54.8 %), and BWT was thicker in this group (p = 0.003). There was a positive correlation between the BWT on initial sonography and duration of cystitis (r² = 0.340). Hydronephrosis developed in 25.8 % of patients with HC, and as HC persisted longer, hydronephrosis occurred more (p = 0.004). In patients with HC after HSCT/BMT, the BWT on initial sonography correlates well with the duration of cystitis. And, longer time of HC develops the risk of hydronephrosis.

Hemorrhagic cystitis after allogeneic hematopoietic cell transplantation: risk factors, graft source and survival

Although hemorrhagic cystitis (HC) is a common complication of allogeneic hematopoietic cell transplantation (alloHCT), its risk factors and effects on survival are not well known. We evaluated HC in a large cohort (n=1321, 2003-2012) receiving alloHCT from all graft sources, including umbilical cord blood (UCB). We compared HC patients with non-HC (control) patients and examined clinical variables at HC onset and resolution. Of these 1321 patients, 219 (16.6%) developed HC at a median of 22 days after alloHCT. BK viruria was detected in 90% of 109 tested HC patients. Median duration of HC was 27 days. At the time of HC diagnosis, acute GVHD, fever, severe thrombocytopenia and steroid use were more frequent than at the time of HC resolution. In univariate analysis, male sex, age <20 years, myeloablative conditioning with cyclophosphamide and acute GVHD were associated with HC. In multivariate analysis, HC was significantly more common in males and HLA-mismatched UCB graft recipients. Severe grade HC (grade III-IV) was associated with increased treatment-related mortality but not with overall survival at 1 year. HC remains hazardous and therefore better prophylaxis, and early interventions to limit its severity are still needed.

BK virus-associated hemorrhagic cystitis after pediatric stem cell transplantation

Hemorrhagic cystitis is a common stem cell transplantation-related complication. The incidence of early-onset hemorrhagic cystitis, which is related to the pretransplant conditioning regimen, has decreased with the concomitant use of mesna and hyperhydration. However, late-onset hemorrhagic cystitis, which is usually caused by the BK virus, continues to develop. Although the BK virus is the most common pathogenic microorganism of poststem cell transplantation late-onset hemorrhagic cystitis, pediatricians outside the hemato-oncology and nephrology specialties tend to be unfamiliar with hemorrhagic cystitis and the BK virus. Moreover, no standard guidelines for the early diagnosis and treatment of BK virus-associated hemorrhagic cystitis after stem cell transplantation have been established. Here, we briefly introduce poststem cell transplantation BK virus-associated hemorrhagic cystitis.

Ultrasonography in the diagnosis of hemorrhagic cystitis - a complication of bone marrow transplantation in pediatric oncology patients

Objective

The aim of this study was to evaluate the usefulness of ultrasonography in the diagnosis of hemorrhagic cystitis following bone marrow transplantation in children.

Material and methods

The study involved an analysis of clinical material and the results of imaging tests performed in 334 patients who underwent hematopoietic cell transplantation. Ultrasonographic findings in 42 patients with hemorrhagic cystitis were analyzed in detail. The ultrasound images served to assess the severity of hemorrhagic cystitis and the results were compared with the clinical assessment of the disease on the Droller scale, as well as the laboratory and endoscopic tests.

Results

In the studied group of patients hemorrhagic cystitis following allogeneic transplantation was diagnosed in 12.5% cases. 73.8% patients received transplants from unrelated donors, 26.2% – from compatible siblings. The study revealed a higher incidence of hemorrhagic cystitis in children above 10 years of age. Grade 3 according to the Droller was diagnosed in 42.9%, grade 2 – in 30.9%, grade 4 – in 14.3%, and grade 1 – in 11.9% patients. The number of ultrasound examinations depended on the clinical symptoms, severity, duration and co-occurrence of other complications following the transplantation and was within the 1–15 range (average: 4.6). Grades 3 and 4 were related to the poor clinical condition of the patients and to their longer hospitalization. During this period there was an increased risk of renal malfunction and acute renal failure, post-inflammatory narrowing of the ureters, hydronephrosis, and in grade 4 the fibrosis of the bladder with reduced bladder capacity. Analyses demonstrated a significant correlation between the ultrasound image of the bladder wall and the clinical severity.

Conclusions

Ultrasound with Doppler options remains the primary diagnostic tool in the evaluation of hemorrhagic cystitis, and is useful in terms of its diagnosis, determination of the severity, and monitoring of the treatment.

Cytomegalovirus is a potential risk factor for late-onset hemorrhagic cystitis following allogeneic hematopoietic stem cell transplantation

Late-onset hemorrhagic cystitis (LOHC) is a common complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is primarily associated with viral infection. We prospectively quantified cytomegalovirus (CMV), BK virus (BKV), and adenovirus in urine and plasma using Q-RT-PCR in 50 consecutive patients to define the relationship between virus and LOHC. Of the 50 patients, 21 developed LOHC at a median of 29 days (range 4-64 days), with a cumulative incidence of 42% (±7.1%). The cumulative incidence of LOHC on day 100 in patients with and without CMV viremia (prior to or at the onset of LOHC) were 56.3% (±8.9%) and 16.7% (±9.1%) (P = 0.018), respectively, and it was 59.3% (±9.8%) and 21.7% (±8.8%) in patients with and without CMV viruria (prior to or at the onset of LOHC) (P = 0.021), respectively. The cumulative incidence of LOHC was also higher in patients with a plasma BKV load increased ≥3 log10 or with a urine BKV load increased ≥4 log10 than those without the increase (P < 0.001). Only one patient with LOHC was tested positive for ADV. Both the univariate and multivariate analyses showed that CMV viremia (HR = 3.461, 95% CI: 1.005-11.922, P = 0.049) and a plasma BKV load that was increased ≥3 log10 (HR = 10.705, 95%CI: 2.469-46.420, P = 0.002) were independent risk factors for the development of LOHC. We conclude that both CMV viremia and an increase of plasma BKV are independent risk factors for LOHC. And the role of CMV viremia was firstly demonstrated.

BK viremia precedes hemorrhagic cystitis in children undergoing allogeneic hematopoietic stem cell transplantation

BK virus is associated with hemorrhagic cystitis after hematopoietic stem cell transplantation (HSCT), although evidence supporting a causal relationship remains limited. Although BK viruria is common after HSCT, BK viremia may better predict clinically significant cystitis, similar to its predictive value for nephropathy after kidney transplantation. We hypothesized that BK viremia would precede hemorrhagic cystitis in a cohort of 88 consecutive children prospectively enrolled to originally study thrombotic microangiopathy in the first 100 days after allogeneic HSCT. Cox regression models with time-varying covariates assessed the association between different BK viremia cutoffs and the development of hemorrhagic cystitis, defined as at least macroscopic hematuria. Subjects with a peak plasma BK viral load 1 to 9999 copies/mL had an adjusted hazard ratio of 4.2 (95% confidence interval (CI), 1.3 to 13.7) for the development of hemorrhagic cystitis. Those with peak BK viremia >100,000 copies/mL had an adjusted hazard ratio of 116.8 (95% CI, 12 to 1136) for cystitis. Other independent risk factors for hemorrhagic cystitis included age >7 years and HHV-6 viremia. Neither graft-versus-host disease nor achieving engraftment increased the risk for cystitis. If therapeutic strategies are found to be effective, these observations may support screening for BK viremia after HSCT, as currently recommended for other DNA viruses.

Hemorrhagic cystitis in children treated with alkylating agent cyclophosphamide: The experience of a medical center in Taiwan

BACKGROUND/PURPOSE

Hemorrhagic cystitis is a common complication with chemotherapeutic alkylating agents. We investigated the possible prognostic factors of cyclophosphamide-induced hemorrhagic cystitis in children.

METHODS

Medical records of children (< 18 years old) with cyclophosphamide-related hemorrhagic cystitis were collected retrospectively from January 2000 to December 2010 in a tertiary care center. We also prospectively enrolled children (< 18 years old) with cyclophosphamide treatment.

RESULTS

The retrospective study consisted of 23 patients whose median age was 11 years. The median day of onset time was 1 day after cyclophosphamide usage. The hemato-oncological diseases included acute leukemia (39.1%), lymphoma (13%), blastoma (13%), sarcoma (13%), aplastic anemia (13%), and others (8.7%). Patients who received bone marrow transplantation (BMT) had significantly longer duration of hemorrhagic cystitis than those who did not receive BMT (p < 0.05). Serum uric acid, checked prior to and after the onset of hemorrhage cystitis, was significantly lower after the development of hemorrhagic cystitis (p < 0.05). In the prospective study, 11 children were enrolled with a median age of 5 years. The urinary nitrite/nitrate and 8-iso-prostaglandin F2α levels increased significantly after cyclophosphamide usage (p < 0.05).

CONCLUSION

Alteration serum uric acid level and BMT could be indicators for severe hemorrhagic cystitis. The elevated levels of urinary nitrite/nitrate and 8-iso-prostaglandin F2α may indicate the essential roles played by nitric oxide syntheses and reactive oxidative stress in cyclophosphamide-induced hemorrhagic cystitis. These findings may help clinicians formulate a better strategy for treating cyclophosphamide-induced hemorrhagic cystitis.

Efficacy and safety of leflunomide for the treatment of BK virus-associated hemorrhagic cystitis in allogeneic hematopoietic stem cell transplantation recipients

BK virus-associated hemorrhagic cystitis (BKV-HC) is a severe complication after allogeneic hematopoietic stem cell transplantation. So far, no specific antiviral drug with proven efficacy has been approved for treating BKV-HC. Leflunomide is an immunosuppressive drug with antiviral activity and has been used in treating BKV-associated nephropathy after renal transplantation. This is the first report on the efficacy and safety of leflunomide in the treatment of BKV-HC. From January 2006 to January 2009, 89 patients received allogeneic hematopoietic stem cell transplantation, and among them, 18 patients were identified as having BKV-HC, with a 20% cumulative incidence. Fourteen patients were treated with oral leflunomide. Three days of 100 mg/day leflunomide was used as loading doses and followed by maintenance doses of 20 mg/day. The urinary BKV-DNA load was monitored weekly by real-time quantitative PCR. The efficacy was evaluated on day 20 after leflunomide treatment. Seven patients (50%) achieved complete remission, 5 patients (35.7%) achieved partial remission, and 2 patients (14.3%) had more than a 1-log reduction in urinary BKV-DNA loads after treatment. During the leflunomide treatment, the graft-versus-host disease of the patients did not progress, and the dosages of the immunosuppressant were reduced simultaneously. One patient discontinued treatment because of intolerable gastrointestinal symptoms. Neutropenia occurred in 2 cases. These preliminary data suggest that leflunomide may be a potentially effective medication for treating BKV-HC without significant toxicity, but evidence supporting its use requires randomized controlled trials.

Improved real-time PCR assay for detection and quantification of all 54 known types of human adenoviruses in clinical samples

Background

Detection and quantification of adenoviruses (AdVs) causing life-threatening complications are important abilities in recognition of infection and management of immunocompromised patients. Due to the rapid increase in the number of known AdV types, most commercial tests for detection and identification of AdVs are outdated.

Material/Methods

We designed an improved, easier and faster real-time quantitative polymerase chain reaction (RQ-PCR) method for detection and quantification of 54 types of human AdVs. A wide validation effort was undertaken to ensure confidence in highly sensitive and specific detection of AdVs in compromised patients. The validation process included evaluation of the method’s suitability and reliability for use in routine diagnostics.

Results

Due to high sensitivity (9.2×10² copies/ml) and broad dynamic range (7 log) we are able to detect specific viral DNA in large amounts of cell-free body fluids. The new assay is characterized by high precision and low variation within and between individual virus tests (CV=0.036%, CV=1.29%), low bias error (4%) and no cross-reactivity with other pathogens.

Conclusions

The implementation of this new assay in clinical and laboratory practice provides a rapid, reliable and less laborious method for detection and monitoring of AdV replication in immunocompromised patients. Moreover, it offers the ability to distinguish between active and latent infection and assess treatment efficiency.

Choreito, a formula from Japanese traditional medicine (Kampo medicine), for massive hemorrhagic cystitis and clot retention in a pediatric patient with refractory acute lymphoblastic leukemia

Hemorrhagic cystitis is critical in patients with hemato-oncological disorders. Unlike adult patients, there are limited modalities and invasive procedures are often not well tolerated in children with poor general conditions. We report a pediatric patient with refractory acute lymphoblastic leukemia who developed life-threatening massive gross hematuria. Along with platelet infusion every other day due to suppressed hematopoiesis, his gross hematuria and clot retention in the bladder were successfully treated with choreito, a formula from Japanese traditional medicine (Kampo medicine). He survived free from hematuria for more than four months. Choreito was well tolerated, and no adverse effects were observed throughout the course.

Emergent Complications in the Pediatric Hematopoietic Stem Cell Transplant Patient

Hematopoietic cell transplantation is the only potentially curative option for a variety of pediatric malignant and nonmalignant disorders. Despite advances in transplantation biology and immunology as well as in posttransplant management that have contributed to improved survival and decreased transplant-related mortality, hematopoietic cell transplantation does not come without significant risk of complications. When patients who have undergone hematopoietic cell transplantation present to the emergency department, it is important to consider a variety of therapy-related complications to optimize management and outcome. In this article, we use clinical cases to highlight some of the more common emergent complications after hematopoietic cell transplantation.

Management of refractory hemorrhagic cystitis following hematopoietic stem cell transplantation in children

HC is a complication associated with HSCT, but occurs rarely in solid organ recipients. The reported incidence varies from <10% to more than 70%. HC is characterized by hemorrhagic inflammation in urinary tract mucosa with symptoms varying from asymptomatic microscopic hematuria to frank hematuria with clot formation and urinary tract obstruction. Early onset HC may be explained by toxicity of chemo- and/or radiotherapy, while multiple factors including viral infections and their interplay seem to be involved in late onset HC. So far, only incidence of cyclophosphamide-associated HC has been reduced with preventive treatment. Likely, once HC is established, the treatment principles are similar regardless of the etiology and depend on the intensity of HC. Prevention of urinary tract obstruction, transfusion support, analgesic, and spasmolytic therapy are generally accepted in HC management. Treatment beyond this conservative approach entails higher risk for side effects, and thus treatment escalation proportional to HC intensity is warranted. No standard and evidence-based treatment escalation algorithm has been widely adopted yet. As severe HC following HSCT is a potentially life-threatening complication, a multidisciplinary and individual approach is required in children suffering from this devastating complication.

Hematuria due to adenoviral infection in bone marrow transplant recipients

Late-onset hemorrhagic cystitis (HC) caused by adenovirus (AdV) infection is a common complication in hematopoietic stem cell transplantation (HSCT) recipients. However, limited information exists regarding adenovirus-associated HC. We report a retrospective study of 84 hematopoietic stem cell transplant recipients that evaluated the incidence and risk factors for AdV-induced HC. The development of HC was strongly related to adenoviral infection (P = .004). Among 13 patients who developed late-onset HC, AdVs were identified as a causative agent in 10 cases. AdV preferentially affected younger (P = .013) and male patients. Affected subjects had been transplanted for either malignant (7/10) or nonmalignant disorders (3/10). Most cases of AdV-hematuria were self-limited single or recurrent mild hemorrhagic episodes (P = .000), occurring at a median of 41 days after transplantation and lasting an average of 4 days. Viral load in patients with AdV-induced HC was similar to infected subjects who did not develop HC (2.5 × 10(3) vs 3.4 × 10(3) copies/mL). We HC occurring before 200 days was associated with a greater risk of a fatal outcome (P = .002) but occurrence of AdV infection did not affect a patient's survival. Our study confirmed the suggestion that non-AdV coinfections may worsen the course of AdV-HC.

Late onset hemorrhagic cystitis in a hematopoietic stem cell recipient: treatment with intravesical hyaluronic acid

HC is a common complication following HSCT. Risk factors include viral infections, cyclophosphamide and busulfan usage, pelvic irradiation, older age at transplantation, allogeneic HSCT and GvHD. The severity of HC ranges from mild hematuria to life-threatening bleeding. Here, we present a seven-and-a-half-yr-old boy with Wiskott-Aldrich syndrome who experienced a late onset Grade III hemorrhagic cystitis following HSCT from his fully matched sibling. A Grade I GvHD localized to skin developed on day +11 and prednisolone therapy was given between the 11th and 22nd d. Myeloid and platelet engraftments were achieved +13 and +16 d, respectively. A gross hematuria began on the 21st post-transplant day. The urine cultures for bacterial or fungal organisms were negative. Urine analysis by PCR revealed a CMV viruria. Following systemic ganciclovir treatment, urinary CMV became negative but hemorrhagic cystitis did not improve. Due to the probability of existing BK virus or adenovirus, two doses of cidofovir were administered intravesically. As he continued to have painful hematuria with large clot formations, two doses of intravesical hyaluronic acid were applied. Macroscopic hematuria resolved within four d after the second dose. Complete remission was achieved on day +77. Finally, intravesical administration of hyaluronic acid seems to be effective and safe and can be a promising treatment in patients suffering from severe and late onset HC.

Pediatric hemorrhagic cystitis

PURPOSE

To review the current literature as it pertains to hemorrhagic cystitis (HC) in the pediatric bone-marrow transplant (BMT) population. By reviewing the pathophysiology of the disease, preventive methods, and therapeutic options, urologists may be better equipped to manage this challenging clinical scenario.

MATERIALS AND METHODS

The HC literature was reviewed using a MEDLINE/PubMed literature search, specifically focusing on the pediatric BMT population as it pertains to the incidence, pathophysiology, prevention, and treatment of HC.

RESULTS

Conservative estimates of HC incidence in recent retrospective studies of pediatric BMT populations still approach 10-20%. Several high-volume pediatric BMT centers have reported contemporary data on their experience with HC providing increased insight into incidence and pathophysiology. Accumulating evidence linking BK virus to HC is a significant development warranting further investigation. Other contributing agents/risk factors need identification in the likely multifactorial etiology of HC. Preventive and therapeutic strategies have made modest advances, but certainly need further validation with prospective randomized studies.

CONCLUSIONS

Pediatric BMT patients are susceptible for HC development despite preventive measures and improved insight into the pathophysiology. Unfortunately, there are no evidence-based treatment guidelines for this difficult clinical issue that frequently requires prolonged care and multiple treatment modalities necessitating judicious patience in the application of more aggressive interventions.

Viral lower urinary tract infections

Lower urinary tract infections (UTIs) are common among the general population and are most often caused by bacterial pathogens. Viruses are an uncommon cause of UTIs in an immunocompetent host; however, viruses are increasingly recognized as the cause of lower UTI, especially hemorrhagic cystitis, among immunocompromised patients. BK virus, adenovirus, and cytomegalovirus are predominant pathogens involved in hemorrhagic cystitis after stem cell and solid organ transplantation, and their early diagnosis and treatment may prevent significant morbidity of hemorrhagic cystitis. The diagnosis of viral lower UTI is based on molecular techniques, and real-time polymerase chain reaction is often the method of choice because it allows for quantification of viral load. Cidofovir is becoming a drug of choice in viral UTIs because it is active against the most common viral pathogens. This review discusses the epidemiology, pitfalls in diagnosis, and current treatment of viral UTIs.

Prevention and management of BK-virus associated haemorrhagic cystitis in children following haematopoietic stem cell transplantation--a systematic review and evidence-based guidance for clinical management

Haemorrhagic cystitis (HC) is a common and, in its severe form, potentially life-threatening complication of Haematopoietic stem cell transplantation (HSCT) in children. Recent data indicate an important role of BK virus reactivation during the time of maximal post-transplant immune suppression in the pathogenesis of late-onset HC. Treatment of HC is mainly symptomatic and often frustrating. To give clinicians guidance on prevention and treatment options and their backing by scientific evidence, we have systematically assessed the available literature and devised evidence-based guidelines. Our comprehensive review demonstrates that evidence for the most commonly used interventions (such as cidofovir, oestrogen, hyperbaric oxygen, bladder instillation with formalin, alum salts or prostaglandin) is very limited. Some of these interventions also carry significant risks. Higher level evidence exists only for 2-mercaptoethane sodium (MESNA) and hyperhydration as a preventative intervention, and for systemic recombinant Factor VII as a treatment to stop acute haemorrhage. Further high-quality studies are required to establish effective and safe prevention and treatment options for HC.

BK-viruria and haemorrhagic cystitis are more frequent in allogeneic haematopoietic stem cell transplant patients receiving full conditioning and unrelated-HLA-mismatched grafts

The influence of conditioning regimen, donor background and HLA matching on development of BK virus (BKV)-associated haemorrhagic cystitis (HC) was examined in 175 allogeneic haematopoietic stem cell transplant (HSCT) patients, undergoing 179 HSCT events. Twenty-seven patients presented late-onset HC, and BK viruria was verified in 23/27 HC events. Seventy-one (40%) HSCTs were performed with myeloablative conditioning (MC), 108 (60%) were performed with reduced intensity conditioning (RIC), 66 (37%) were performed with a related donor (RD) grafts and 113 (63%) with an unrelated donor (URD) graft. BK viruria was more common during HC, than non-HC events, after MC as compared to RIC (both P<0.001), and with an HLA-mismatched donor (P<0.01). By multivariate logistical regression analysis, independent risk factors for HC were BKV (OR 6.7; 95% CI 2.0-21.7; P=0.001), MC (OR 6.0; 95% CI 2.1-17.3; P<0.001) and URD (OR 3.4; 95% CI 1.1-10.6; P=0.03). However, when analysing HSCT performed with URD or RD grafts separately, BKV (OR 8.5; 95% CI 1.8-19.3; P=0.004) and MC (OR 5.9; 95% CI 1.3-11.3; P=0.009) increased the risk for HC only with a URD, but not with an RD graft.

A prospective study of BK-virus-associated haemorrhagic cystitis in paediatric patients undergoing allogeneic haematopoietic stem cell transplantation

We investigated the incidence, risk factors and outcome of haemorrhagic cystitis (HC) in paediatric patients undergoing HSCT and the predictive value of BK viruria and viraemia for developing HC. Over a period of 54 months, 74 patients were recruited. The cumulative incidence of HC was 22%. Among 15 patients prospectively monitored for BK viruria and viraemia, four patients developed HC of grade > or =II. This group, which had two consecutive BK positive samples, showed a sensitivity of 100%, a specificity of 82%, a positive predictive value of 67%, and negative predictive value of 100% for developing HC. Analysed by a receiver-operator characteristic curve (ROC), a urine BK load >9 x 10(6) genomic copies/ml had a sensitivity of 95% and specificity of 90%; while a blood BK load >1 x 10(3) genomic copies/ml had a sensitivity of 40% and a specificity of 93% for HC, respectively. In univariate analysis, BK positivity was the only factor significantly associated with HC. After a median follow-up of 1.8 years, patients with HC showed a lower overall survival, 40 vs 65%, P 0.01, and a lower event-free survival, 42 vs 62%, P 0.03, compared to patients without HC. We conclude that BK detection in urine and/or plasma is a specific predictor for developing HC.

Hemorrhagic cystitis in a patient receiving conventional doses of dacarbazine for metastatic malignant melanoma: case report and review of the literature

INTRODUCTION

Hemorrhagic cystitis is a potentially life-threatening complication in patients receiving cancer therapy. This urologic emergency is commonly associated with the chemotherapeutic use of oxazaphosphorine alkylating agents. This report describes a case of hemorrhagic cystitis associated with dacarbazine treatment.

CASE SUMMARY

A 63-year-old man with asymptomatic metastatic malignant melanoma received 3 cycles of dacarbazine (600-850 mg/m2) monochemotherapy, each 3 weeks apart. Two weeks after the third cycle, he presented with gross hematuria and mild dysuria. Physical examination revealed no significant finding. Hematuria was confirmed by urinalysis, and urinary infection was excluded by repeated urine cultures. Ultrasonography revealed diffuse bladder wall thickening with no discrete mass or ulceration. Cystoscopy findings revealed generalized inflammation and edema of the mucosa of the bladder, confirming the diagnosis of hemorrhagic cystitis. The patient's gross hematuria continued for 2 weeks and then completely resolved with supportive care. Two weeks after complete resolution, the patient experienced 2 transient episodes of gross hematuria that lasted a few hours and subsided spontaneously.

DISCUSSION

Dacarbazine is currently considered the standard first-line treatment in patients with advanced malignant melanoma. At standard prescribed doses (a single dose of 850-1000 mg/m2 or 250 mg/m2 for 5 days per cycle), dacarbazine is a reasonably well tolerated chemotherapeutic drug; nausea, vomiting, and myelosuppression are the most common adverse effects. Association of dacarbazine with hemorrhagic cystitis has not been reported previously (in a PubMed literature search from 1950-2006), and only 1 case report associates temozolomide (an analog of dacarbazine) with hemorrhagic cystitis. Based on the Naranjo adverse drug reactions probability scale, an objective assessment revealed dacarbazine to be a probable cause of hemorrhagic cystitis in this case.

CONCLUSIONS

This case report suggests that dacarbazine at conventional doses was a probable cause of hemorrhagic cystitis. Regular urinalysis and early intervention are recommended, as a means of detecting early hematuria and subsequently reducing or discontinuing dacarbazine treatment. Adequate hydration before, during, and after dacarbazine administration may be useful in preventing this complication.

Risk factors and treatment of hemorrhagic cystitis in children who underwent hematopoietic stem cell transplantation

A retrospective cohort of 163 children with 171 hematopoietic stem cell transplantation (HSCT) performed during Mar. 1992-Dec. 2005 were analyzed to evaluate the incidence, risk factors, management, and outcome of hemorrhagic cystitis (HC). Fourteen patients (8.2%) developed HC (6 boys, median age 6.6 years) at 0-166 days after HSCT (median 25 days), and lasted for 3-96 days (median 26 days). Older age at transplant (median 11.0 vs. 6.4 years, P = 0.013), allogeneic transplant (OR = 4.4, P = 0.02), cyclophosphamide-containing conditioning (OR = 4.87, P = 0.008), moderate-to-severe acute graft-versus-host disease (GVHD) (OR = 3.56, P = 0.025) and hepatic GVHD (OR = 3.62, P = 0.017) were associated with higher risks of HC in univariate but not multivariate analyses. While estrogen was ineffective in most patients, intravesical formalin, which was used in five patients, was found to be a very effective yet safe treatment for intractable HC. Patients with HC had longer hospital stay (median 175 vs. 88 days, P = 0.004). HC resolved after treatments in all cases but eight of the 14 patients subsequently died of other complications of HSCT. In conclusion, HC is a serious complication of allogeneic HSCT. Treatment with intravesical formalin appears effective and safe and can be considered early in severe HC to reduce the risk of morbidity and mortality.

[Intensive care support of patients after stem cell transplantation]

Within the hematologic therapy procedures, stem cell transplantation (SCT) represents the most extensive and invasive intervention. Those patients have certain risks for several bacterial, viral, as well as fungal infections during the different stages of transplantation. Especially in allogenic transplantation, discrimination of non-infectious, mostly immunologic complications like graft-versus-host reactions or VOD (veno-occlusive disease) is crucial, and often represents a therapeutic challenge. An adequate intensive care therapy of these patients can only be achieved with the knowledge of the specific complications of SCT. This review starts with an overview of the SCT stages with their corresponding infectious and noninfectious complications, followed by the discussion of organ specific pulmonary, renal, cardiac, gastrointestinal, hepatic and neurological complications of stem cell transplantation.

Viral lower urinary tract infections

Lower urinary tract infections (UTIs) are common among the general population and are most often caused by bacterial pathogens. Viruses are an uncommon cause of UTIs in an immunocompetent host; however, viruses are increasingly recognized as the cause of lower UTI, especially hemorrhagic cystitis, among immunocompromised patients. BK virus, adenovirus, and cytomegalovirus are predominant pathogens involved in hemorrhagic cystitis after stem cell and solid organ transplantation, and their early diagnosis and treatment may prevent significant morbidity of hemorrhagic cystitis. The diagnosis of viral lower UTI is based on molecular techniques, and real-time polymerase chain reaction is often the method of choice because it allows for quantification of viral load. Cidofovir is becoming a drug of choice in viral UTIs because it is active against the most common viral pathogens. This review discusses the epidemiology, pitfalls in diagnosis, and current treatment of viral UTIs.

Critical care considerations of hematopoietic stem cell transplantation

OBJECTIVE

To review the available clinical data on the critical care complications of hematopoietic stem cell transplantation (HSCT).

DATA SOURCE

The MEDLINE database and references from the identified articles related to the critical care in HSCT.

CONCLUSION

HSCT is an important treatment for a variety of malignant and nonmalignant conditions. The procedure is, however, limited by significant complications that may involve every organ of the body. Up to 40% of HSCT recipients are admitted to the intensive care unit as a result of severe complications related to the transplantation. The outcome of those critically ill patients has been traditionally poor. However, recent advances in the transplantation procedure, diagnostic studies, antimicrobial prophylaxis and therapy, and intensive care unit care have improved the outcome of these patients. The increasing number of HSCTs performed annually, the unique complications that develop in these patients, and the improvement in the intensive care unit outcome make knowledge about the critical care aspect of HSCT an essential part of the current practice of critical care medicine.