Design and validation of a diagnostic score for biliary atresia

BACKGROUND & AIMS

The dilemma of early diagnosis of biliary Atresia (BA), particularly distinguishing it from other causes of neonatal cholestasis is challenging. The aim was to design and validate a scoring system for early discrimination of BA from other causes of neonatal cholestasis.

METHODS

A twelve-point scoring system was proposed according to clinical, laboratory, ultrasonographic, and histopathological parameters. A total of 135 patients with neonatal cholestasis in two sets were recruited to design (n=60) and validate (n=75) a scoring system. Parameters with significant statistical difference between BA (n=30) and non-BA (n=30) patients in the design set were analyzed by logistic regression to predict the presence or absence of BA then a scoring system was designed and validated.

RESULTS

The total score ranged from 0 to 37.18 and a cut-off value of >23.927 could discriminate BA from other causes of neonatal cholestasis with sensitivity and specificity of 100% each. By applying this score in the validation set, the accuracy was 98.83% in predicting BA. The diagnosis of BA was proposed correctly in 100% and the diagnosis of non-BA was proposed correctly in 97.67% of patients. By applying this model, unnecessary intraoperative cholangiography would be avoided in non-BA patients.

CONCLUSIONS

This scoring system accurately separates infants with BA and those with non-BA, rendering intraoperative cholangiography for confirming or excluding BA unnecessary in a substantial proportion of patients.

Common misdiagnoses of biliary atresia

OBJECTIVES

Discrimination of biliary atresia (BA) from other causes of neonatal cholestasis (NC) is challenging. We aimed to analyze the clinicopathological findings in cholestatic infants who were provisionally diagnosed with BA and then excluded by intraoperative cholangiography compared with those with a definitive diagnosis of BA and to shed light on common misdiagnoses of BA.

METHODS

We retrospectively analyzed the data of infants diagnosed preoperatively with BA and referred to surgery between the years 2009 and 2013. On the basis of intraoperative cholangiography results, infants were divided into those with a definitive diagnosis of BA and those misdiagnosed with BA.

RESULTS

Out of 147 infants, there was a misdiagnosis of BA in 10 (6.8%) infants. Alanine transaminase was significantly higher in the non-BA group, whereas other clinical and laboratory findings were comparable in both groups. Hepatomegaly and abnormal gallbladder in ultrasound, and ductular proliferation and advanced grades of portal fibrosis in liver biopsy were significantly higher in infants with BA. However, giant cells were more common in the non-BA infants. Nonetheless, the frequency of clay stool, hepatomegaly, abnormal gallbladder, ductular proliferation, and advanced portal fibrosis was remarkable (100, 70, 40, 70, and 50%, respectively) in the misdiagnosed infants. The misdiagnoses were idiopathic neonatal hepatitis, progressive familial intrahepatic cholestasis type 3, cytomegalovirus hepatitis, Alagille syndrome, and a cholangitic form of congenital hepatic fibrosis.

CONCLUSION

A meticulous preoperative workup should be performed to exclude other causes of NC even if signs of BA are present, especially if features such as giant cells in histopathology are present. This involves completing the NC workup in parallel involving all common causes of NC rather than performing them in series to avoid loss of valuable time and efforts.

Serological markers of autoimmunity in children with hepatitis A: relation to acute and fulminant presentation

OBJECTIVES

Hepatitis A virus (HAV) infection tends to be a self-limiting disease without serious sequelae, but fulminant hepatitis, with a high mortality, develops in 0.1-0.2% of the cases. Sometimes, HAV infection precipitates autoimmune hepatitis (AIH). We aimed to assess the frequency and clinical significance of serologic markers of autoimmunity during hepatitis A infection with an acute or fulminant presentation compared with those in AIH.

METHODS

The study included 126 children: 46 with HAV infection (33 with acute and 13 with fulminant presentation), 53 with AIH, and 27 healthy controls. In all, we measured autoantibodies titer (antinuclear antibody, antismooth muscle antibody, and liver kidney microsomal antibody-1) and serum gammaglobulins.

RESULTS

Autoantibodies were detected in the majority of HAV (63.1%) and AIH (79.2%) groups, but in none of the controls. Gammaglobulins were significantly higher in the HAV group (1.93±0.57 g/dl) than in the controls (1.32±0.29 g/dl), but lower than that in the AIH group (2.93±1.2 g/dl) (P<0.0001 for all). In the HAV group, gammaglobulins were significantly higher in those with fulminant (2.21±0.46 g/dl) than in those with acute presentation (1.82±0.57 g/dl) (P=0.019), but comparable with that in AIH (P=0.095). Gammaglobulins correlated significantly with disease severity in both HAV and AIH groups.

CONCLUSION

Hypergammaglobulinemia and a high occurrence of autoantibodies are encountered in HAV infection. This may support the immunological basis of its pathogenesis. Moreover, the higher gammaglobulins in fulminant HAV, with an insignificant difference from that in AIH, suggest that a more aggressive immunological reaction is related to this presentation.

Urinary urobilinogen in biliary atresia: A missed, simple and cheap diagnostic test

AIM

Early diagnosis of biliary atresia (BA) is of utmost importance for good outcome; however, it is sometimes difficult due to the overlapping diagnostic test results with other causes of neonatal cholestasis. Moreover, many diagnostic tests are costly, invasive and not available in all centers, especially in developing countries. So, we aimed to investigate the diagnostic performance of urinary urobilinogen; an easy, cheap test that was not tested before in BA.

METHODS

Seventy-five infants divided into three age- and sex-matched groups (BA, non-BA cholestasis and healthy control group) were recruited for the study. Each group comprised 25 infants. Urinary urobilinogen was measured for all infants using the modified Ehrlich's method.

RESULTS

Urinary urobilinogen was significantly lower in the BA group (0.31 ± 0.25 mg/dL) than both of the non-BA cholestasis (2.08 ± 3.48 mg/dL) and healthy control (0.53 ± 0.64 mg/dL) groups at P < 0.0001 and P < 0.001, respectively. Urinary urobilinogen at a cut-off value of 0.32 mg/dL or less can differentiate BA from other non-BA cholestasis with a sensitivity of 88% and a specificity of 72%. When this cut-off value was combined with γ-glutamyltransferase (γ-GT) at a cut-off value of 363 U/L or more, BA could be differentiated from other cholestatic disorders with a sensitivity of 80% and specificity of 100%. On the other hand, dipstick test could not differentiate between BA and non-BA cholestasis (P = 0.396).

CONCLUSION

Urinary urobilinogen is a simple, non-invasive, cheap, sensitive and specific marker, especially if combined with γ-GT, which can be used in diagnosis of BA, especially in developing countries.

Hepatic progenitor cells in children with chronic hepatitis C: correlation with histopathology, viremia, and treatment response

OBJECTIVE

Hepatic progenitor cells (HPCs) are bipotential stem cells that can differentiate towards the hepatocytic and cholangiocytic lineages. Many studies have investigated HPCs in adults with hepatitis C virus infection; however, none has been carried out in the pediatric population. Therefore, this work aimed to investigate HPCs expansion in children with chronic hepatitis C (CHC) and its correlation with histopathology, viremia, and treatment response.

PATIENTS AND METHODS

Eighty children with CHC, 73 of whom received interferon-based therapy, were recruited. Sections of their liver biopsies were prepared for immunostaining of HPCs using cytokeratin-7 antibody.

RESULTS

HPCs were expanded in most children (81.3%) with CHC. Expansion occurred in two forms: intraparenchymal isolated hepatic progenitor cell form and periportal ductular reaction form. There was a significant increase in HPCs expansion in higher stages of fibrosis (50, 81.8, and 100% in no, mild, and moderate fibrosis, respectively, with P=0.029). Also, HPCs expansion increased with increased grade of necroinflammatory activity (0, 77.8, 81.8, and 100%, in no, minimal, mild, and moderate activity, respectively), although this was statistically insignificant. Moreover, a significant positive correlation was found between the isolated hepatic progenitor cell number and ductular reaction grade (r=0.755, P<0.0001), and both were significantly correlated with the level of viremia and the grade of necroinflammatory activity. Finally, HPCs expansion was not related to the treatment response.

CONCLUSION

The relationship of HPCs with both the severity of hepatitis and the stage of fibrosis may be because of a role of HPCs in their pathogenesis.

SOX9 in biliary atresia: New insight for fibrosis progression

BACKGROUND

Liver fibrosis is a hallmark determinant of morbidity in biliary atresia (BA) even in successfully operated cases. Responsible factors for this rapid progression of fibrosis are not completely defined. Aberrant expression of the transcription factor SOX9 and hepatic progenitor cells (HPCs) proliferation have roles in fibrogenesis in cholestatic disorders. However, they were not investigated sufficiently in BA. We aimed to delineate the relation of SOX9 and HPCs to fibrosis and its progression in BA.

METHODS

Forty-eight patients with BA who underwent an initial diagnostic liver biopsy (LB) and consequent intraoperative LB were recruited and compared to 28 cases with non-BA cholestasis that had an LB in their diagnostic workup. Liver fibrosis, tissue SOX9 and HPC expressions were studied in both BA and non-BA-cholestasis cases. Liver fibrosis, SOX9, and HPCs' dynamic changes in BA cases were assessed. Relation of fibrosis and its progression to SOX9 and HPCs in BA was assessed.

RESULTS

SOX9 and HPCs in ductular reaction (DR) form were expressed in 100% of BA and their grades increased significantly in the second biopsy. The rapidly progressive fibrosis in BA, represented by fibrosis grade of the intraoperative LB, correlated significantly to SOX9-DR and HPC-DR at the diagnostic (r = 0.420, P = 0.003 and r = 0.405, P = 0.004, respectively) and the intraoperative (r = 0.460, P = 0.001 and r = 0.467, P = 0.001, respectively) biopsy. On the other hand, fibrosis, SOX9-DR, and HPC-DR were significantly lower in non-BA cases at a comparable age (P < 0.001, P = 0.006, and P = 0.014, respectively).

CONCLUSIONS

Fibrosis in BA is rapidly progressive within a short time and is significantly correlated to SOX9 and HPCs. Assessment of targeting SOX9 and HPCs on fibrosis progression is warranted.

P-Selectin (CD62P) Expression in Liver Tissue of Biliary Atresia: A New Perspective in Etiopathogenesis

OBJECTIVES

The etiology of biliary atresia (BA) is still elusive. Inflammation plays a key role in bile duct and liver injury. The recruitment and accumulation of inflammatory cells is largely dependent on adhesion molecules. We aimed to investigate P-selectin (CD62P) expression in liver tissue in patients with BA compared with other neonatal cholestatic disorders.

METHODS

The study included 63 infants with neonatal cholestasis in 2 groups: BA group (n = 32) and non-BA group (n = 31) with non-BA cholestatic disorders as controls. Demographic, clinical, laboratory, ultrasonographic, and histopathological parameters were collected. P-selectin immunostaining was performed. Immunostaining in bile duct epithelium, cellular infiltrate, and vascular endothelial cells were scored as positive or negative.

RESULTS

The frequency of P-selectin-positive endothelium, platelets, and bile duct epithelium was significantly higher in the BA group (72%, 72%, and 63%, respectively) than in the non-BA group (32%, 16%, and 13%, respectively) with P of 0.002, <0.0001, and <0.0001, respectively. Few mononuclear cellular infiltrates in portal tract expressed P-selectin and were comparable in both groups (P = 0.932). Of interest, the platelet count was significantly higher in the BA group (532 ± 172) than in the non-BA group (406 ± 158), and 68.8% of the BA group had thrombocytosis versus 25% in the controls (P = 0.001 for both).

CONCLUSIONS

The significant expression of P-selectin in endothelium, platelets, and bile duct epithelium in patients with BA suggests a potential role for this adhesion molecule in the pathogenesis of this devastating neonatal hepatic disorder. It further suggests that platelets in BA are activated and may have a role in the inflammatory process in BA.

Serum ferritin in neonatal cholestasis: A specific and active molecule or a non-specific bystander marker?

BACKGROUND

Serum ferritin (SF) and consequently hepatic iron have long been considered important in liver fibrosis progression. They have been studied in different liver diseases with no previous reports in neonatal cholestasis (NC). This study aimed to measure SF in different etiologies of NC and investigate its relation to hepatic iron and fibrosis.

METHODS

SF was measured in 75 infants, including 50 with NC and 25 with sepsis. SF was compared between these two groups. Biochemical parameters, hepatic iron grades, and liver fibrosis and other histopathological characteristics and correlated with SF were assessed in NC group. Finally, a comparison between intrahepatic cholestasis and obstructive etiology was performed.

RESULTS

SF was elevated in NC (1598 ± 2405 ng/mL) with no significant difference from those with sepsis (P = 0.445). NC and sepsis constituted augmenting factors leading to more elevation of SF (2589 ± 3511 ng/mL). SF was significantly correlated with hepatic iron grades (r = 0.536, P < 0.0001) and a cut-off value of 803.5 ng/mL can predict higher grades (≥ grade 3) of iron deposition with sensitivity of 100%, specificity of 70% and accuracy of 85%. Moreover, SF was significantly higher (P < 0.0001) in those with intrahepatic cholestasis (2602 ± 3154 ng/mL) and their prevalent pathological findings of giant cell transformation (P = 0.009) and hepatocyte swelling (P = 0.023) than those with obstructive etiology (672 ± 566 ng/mL) and their prevalent pathological findings of ductular proliferation (P = 0.003) and bile plugs (P = 0.002). SF was unrelated to the grade of liver fibrosis (P = 0.058).

CONCLUSIONS

SF is non-specifically elevated in NC, with positive correlation to hepatic iron grades. SF ≥ 803.5 ng/mL can predict higher grades (≥ grade 3) of hepatic iron. However, an active role of increased SF and hepatic iron in disease progression remains questionable.

Temporal histopathological changes in biliary atresia: A perspective for rapid fibrosis progression

INTRODUCTION AND OBJECTIVES

Biliary atresia (BA) is characterized by rapid progression of fibrosis with no definite causes. Histopathological findings have been extensively described, but very few studies have assessed temporal changes in BA. Understanding these short-term changes and their relationship with fibrosis progression could have an impact on ameliorating rapid fibrogenesis. We aimed to study the relationship between temporal histopathological changes and fibrosis progression in BA within a short time interval.

PATIENTS AND METHODS

Forty-nine infants with BA who underwent Kasai portoenterostomy, a diagnostic liver biopsy, and an intraoperative liver biopsy were recruited. Histopathological characteristics of the two biopsies were examined. Temporal histopathological changes were assessed by comparing the two types of biopsies. Correlation of temporal changes in fibrosis with age, interval between biopsies, laboratory profiles, and temporal histopathological changes were studied.

RESULTS

In the univariate analysis, bile ductular proliferation (BDP), portal infiltrate, giant cells, hepatocellular swelling, and fibrosis showed significant temporal changes within a short interval (5-31 days). BDP and fibrosis showed the most frequent increase in their grades (32/49 and 31/49 cases, respectively). In the multivariate analysis, BDP was the only independent pathological feature showing a significant temporal increase (p = 0.021, 95% confidence interval: 1.249-16.017). Fibrosis progression was correlated with temporal changes in BDP (r = 0.456, p = 0.001), but not with age (p = 0.283) or the interval between the biopsies (p = 0.309).

CONCLUSIONS

Fibrosis in BA progresses rapidly and is significantly correlated with BDP. Assessment of targeting BDP as an adjuvant medical therapy is recommended.

Steroid therapy in children with fulminant hepatitis A

Fulminant hepatic failure is a life-threatening disease. Hepatitis A virus (HAV) can cause fulminant hepatic failure and death in about 0.2% of cases. Extensive destruction of infected hepatocytes by immune-mediated lysis is thought to be the cause. We aimed to evaluate the use of steroid therapy in children with fulminant HAV. This study included 33 children with fulminant HAV in two groups. Steroid group: comprised of 18 children who received prednisolone (1 mg/kg/d) or its equivalent dose of methylprednisolone, and the nonsteroid group: comprised another 15 children who did not receive steroid therapy. Age and sex were matched for both groups (P > .05), and they were comparable regarding baseline clinical and laboratory characteristics. Of the steroid group, 15 patients survived and 3 died, while in the nonsteroid group, 4 patients survived and 11 died (P = .001). Of the living patients, 15 of 19 (78.9%) received steroids while only 3 of 14 (21.4%) of the dead patients received steroids (P = .001). Stepwise regression analysis showed that steroid therapy was the only independent variable associated with recovery (P = .001). Steroid therapy in children with fulminant HAV associated significantly with improved outcome and survival. Future studies on a larger population size are strongly recommended.

Adequacy criteria of Tru-cut needle liver biopsy in neonatal cholestasis

INTRODUCTION AND OBJECTIVES

Assessment of liver biopsy sample adequacy criteria is essential to avoid sampling errors in patients with diffuse liver pathology. Many studies have evaluated these criteria in adults; however, no previous studies have been performed on neonatal liver disorders. We aimed to assess the adequacy criteria of Tru-cut needle liver biopsy samples in infants with neonatal cholestasis (NC).

METHODS

In a retrospective analysis of infants who underwent liver biopsy for NC within a one-year duration, 58 specimens were recruited. The core lengths after fixation were measured. All samples were acquired with a 16-gauge (G) Tru-cut needle. Serial shortening of these samples was performed to define the smallest core length that gives representative parenchyma that could determine the activity grade and fibrosis stage reported by larger cores.

RESULTS

It was found that a 4-mm core length with a complete portal tract (CPT) number of 8±3 could adequately assess the NC activity grade. In addition, a 6-mm core length with a CPT number of 11±3 could adequately estimate NC fibrosis stage.

CONCLUSIONS

The adequacy criteria of liver tissue samples for the accurate assessment of NC are different from those defined for adult diffuse liver pathology. At least a 4-mm core length with a CPT number of 8±3 and a 6-mm core length with a CPT number of 11±3 acquired by a 16-G Tru-cut needle should be used to assess NC activity grade and fibrosis stage, respectively.

Serum Adiponectin, Vitamin D, and Alpha-Fetoprotein in Children with Chronic Hepatitis C: Can They Predict Treatment Response?

Background & Aims. The currently available treatment for chronic hepatitis C (CHC) in children is costly and with much toxicity. So, predicting the likelihood of response before starting therapy is important. Methods. Serum adiponectin, vitamin D, and alpha-fetoprotein (AFP) were measured before starting pegylated-interferon/ribavirin therapy for 50 children with CHC. Another 21 healthy children were recruited as controls. Results. Serum adiponectin, vitamin D, and AFP were higher in the CHC group than healthy controls (p < 0.0001, p = 0.071, and p = 0.87, resp.). In univariate analysis, serum adiponectin was significantly higher in responders than nonresponders (p < 0.0001) and at a cutoff value ≥8.04 ng/mL it can predict treatment response by 77.8% sensitivity and 92.9% specificity, while both AFP and viremia were significantly lower in responders than nonresponders, p < 0.0001 and p = 0.0003, respectively, and at cutoff values ≤3.265 ng/mL and ≤235,384 IU/mL, respectively, they can predict treatment response with a sensitivity of 83.3% for both and specificity of 85.7% and 78.6%, respectively. In multivariate analysis, adiponectin was found to be the only independent predictor of treatment response (p = 0.044). Conclusions. The pretreatment serum level of adiponectin can predict the likelihood of treatment response, thus avoiding toxicities for those unlikely to respond to therapy.

Epidemiology of acute liver failure in Egyptian children

Background

Acute liver failure (ALF) is a serious condition that refers to the development of synthetic function impairment after severe acute liver injury in an individual without pre-existing liver disease. Understanding the epidemiology of ALF in children constitutes a cornerstone in its preventive and treatment plans. Nevertheless, there is a lack of information about its epidemiology in Egypt.

Objective

The aim of this study was to assess the epidemiologic data of ALF in Egyptian children.

Patients and methods

The medical records of children with ALF aged from 6 months to 18 years who were admitted from 2015 to 2020 were analyzed to identify the patient’s epidemiologic, laboratory, and investigational data together with their outcome.

Results

The study included 154 patients who fulfilled the definition of ALF were included. Their age ranged from 7 months to 17 years, with a median of 5.8 years. Hepatitis A virus (HAV) was the most commonly identifiable etiology (37.7%). Mortality was the outcome for 73 patients (47.4%). The prognostic factors associated with mortality were elevated international normalized ratio (INR), total bilirubin (TB), creatinine, and ammonia levels at presentation with cutoff values (2.97, 21.15, 0.385, and 212, respectively).

Conclusion

Hepatitis A virus is the most commonly identified etiology of ALF in Egyptian children. The mortality rate is high, and most of the deaths occurred early in the first 5 days of admission. So, early preparation for liver transplantation is recommended. Higher values of INR, TB, and creatinine above the cutoff levels at presentation may be potential markers for predicting death in affected children.

Hepatic hydrothorax in the absence of ascites in a child with autoimmune hepatitis: Successful management with octreotide and pleurodesis

Hepatic hydrothorax is a rare complication of liver cirrhosis and portal hypertension. It carries a diagnostic and therapeutic difficulty especially if occurring in the absence of ascites. We report a nine-year-old child with autoimmune hepatitis type 1, who presented with a right-sided hepatic hydrothorax in the absence of ascites. The patient was treated successfully with diuretics, octreotide and pleurodesis together with immunosuppressive therapy for autoimmune hepatitis. There was no recurrence of effusion after a long follow-up duration. In conclusion, hepatic hydrothorax should be considered in the differential diagnosis of pleural effusion occurring in children with cirrhotic liver, whether associated with ascites or not. Octreotide as a splanchnic vasoconstrictor can be used in establishing the diagnosis and in the treatment of hepatic hydrothorax. The need for liver transplantation in such patients may be avoided when the liver disease can be treated specifically.

Transforming growth factor-βeta and interleukin-1βeta in children with acute liver failure: pathophysiology and outcome perspectives

Background

The exact pathophysiology of acute liver failure (ALF) in children is not well defined. Some animal studies showed increased cytokines as a driving force for its occurrence with defective similar human studies. This study aimed to measure the plasma level of the pro-inflammatory cytokine (IL-1β) and anti-inflammatory cytokine (TGF-β) in children with ALF and assess their relation to the outcome and complications.

Patients and methods

It is a prospective case–control study that included 25 children with ALF, 20 children with self-limited acute hepatitis A, and 10 healthy children as control groups. Plasma samples were collected at presentation to measure IL-1β and TGF-β levels using the ELISA technique.

Results

Higher levels of IL-1β and TGF-β were found in ALF than acute hepatitis A group with insignificant differences. TGF-β was significantly higher in ALF and acute hepatitis groups than the healthy control group (p-value < 0.05). Moreover, the TGF-β/IL-1β ratio showed no significant difference among the studied groups despite trending to be higher in ALF. TGF-β and TGF-β/IL-1β ratio were higher in the survived while IL-1β was higher in the deceased cases but all did not reach a significant level. When the TGF-β/IL-1β ratio was ≥ .8, the survival probability in ALF cases was 100%. In the ALF group, IL-1β was significantly higher in those who were complicated with brain edema and circulatory failure (p-value < 0.05). A model score designed of TGF-β/IL-1β ratio, age, encephalopathy, and brain edema can predict mortality in ALF cases at a cutoff value of − 1.2 with a sensitivity of 100%.

Conclusion

Increased cytokines in ALF with an imbalance between the pro- and anti-inflammatory cytokines could have a role in the pathogenesis and the outcome of ALF. TGF-β/IL-1β ratio is trending to be higher in survived ALF cases and a model score including it can predict the mortality. The baseline level of IL-1β in ALF is significantly higher in those who develop brain edema and circulatory failure, so experimental studies of its targeting are warranted.

Predictors of azathioprine toxicity in children with autoimmune hepatitis

Aim of the study

Azathioprine (AZA) is an important steroid-sparing drug in the management of autoimmune hepatitis (AIH). Avoidance of its adverse events that could be severe and carry a risk of mortality in a few cases is important, preferably with cheap and easy assessments that could be feasible in developing countries with the unavailability of molecular assays. Assessment of thiopurine methyltransferase (TPMT), the key enzyme for the inactivation of AZA, as a predictor of AZA toxicity had been a matter of conflict. This work aimed to study the role of TPMT serum level assessment and other host-, disease-, and treatment-related factors in predicting AZA toxicity.

Material and methods

Sixty-six children with AIH, divided into two groups, were recruited. Group 1 included twelve children with AZA toxicity and group 2 included fifty-four children without AZA toxicities. Both groups were compared for demographic, clinical, laboratory, histopathological, and treatment-related factors, and serum TPMT level, measured by ELISA.

Results

TPMT serum level was comparable in both groups (p = 0.363). Duration of treatment until enzyme normalization and duration of AZA therapy were significantly associated with AZA toxicity (p = 0.007 and p = 0.01, respectively). At the first follow-up treatment with AZA, total leucocyte count (TLC) and neutrophil counts were significantly lower in group 1 (p = 0.005 and p = 0.002, respectively). Moreover, the percentage reduction of TLC and neutrophil counts were significantly higher in group 1 (p < 0.001, for both).

Conclusions

Monitoring for AZA adverse events in those with the defined predictors of AZA-related adverse events is more important than TPMT assessment.