Wolman's Disease: A Rare Cause of Infantile Cholestasis and Cirrhosis

Liver cirrhosis in infancy can be secondary to various etiologies such as biliary atresia, familial cholestatic and metabolic disorders. Wolman's disease (WD) is a lysosomal storage disorder caused by the absence of lysosomal acid lipase enzyme activity and a significant association with infantile cholestasis and cirrhosis. We encountered an infant presenting with advanced cirrhosis and decompensation having splenomegaly for which the underlying etiology was found to be WD and the diagnostic clue came from abdominal X-ray showing bilateral adrenal calcifications. The diagnosis was confirmed by genetic analysis. The outcome was poor and died before 6 months of age without enzyme replacement therapy or hematopoietic stem cell transplantation.

Liver Transplantation: A Safe and Definitive Alternative to Lifelong Nitisinone for Tyrosinemia Type 1

OBJECTIVES

To report the experience of liver transplantation (LT) for tyrosinemia type 1 (TT-1).

METHODS

Clinical data of children with TT-1 who underwent living donor LT between July 2009 and May 2020 were retrospectively analyzed. Data included pre-LT nitisinone therapy, graft type, post-LT complications, HCC incidence, and graft/patient survival.

RESULTS

Nine children were diagnosed with TT-1 at a median age of 12 mo (6-54 mo). Nitisinone was started in 6 patients at a median age of 15 mo (6-42 mo), but all had frequent interruption of therapy due to logistics with drug procurement including its cost. Median age at transplantation was 5 y (2-11 y). Explant liver showed HCC in 5 patients (55% of total cohort). The graft and patient survival are 100% with median follow-up of 58 mo (24-84 mo).

CONCLUSION

LT is curative for TT-1 and excellent results can be obtained in experienced centers. This is especially favorable in countries with limited resources where the cost of medical therapy is highly prohibitive, with lifelong diet restrictions and unclear long-term risk of HCC.

To Access the Role of Serum Procalcitonin in Predicting the Severity of Acute Pancreatitis

Background Acute Pancreatitis remains a common disorder with devastating consequences in severe form of disease. In this study we assessed serum procalcitonin for early prediction of severity of acute pancreatitis and compared it with multiple scoring systems and biomarkers. Objective This is a prospective comparative study in which 125 patients with diagnosis of acute pancreatitis were enrolled. All blood samples and imaging studies were obtained within 24-72 hours of admission and the severity was predicted. Method This is a prospective comparative study in which 125 patients with diagnosis of acute pancreatitis were enrolled. All blood samples and imaging studies were obtained within 24-72 hours of admission and the severity was predicted. Result Acute pancreatitis was graded severe in 54 patients and mild in 71 patients as per the Atlanta criteria. Receiver operating characteristic curve showed the area under curve of serum procalcitonin was higher (area under curve: 0.887, Confidence interval: 0.825-0.948) compared to computed tomography severity index scoring system (Area under curve: 0.841, Confidence interval: 0.771-0.911), Ranson's score (Area under curve: 0.796, Confidence interval: 0.715-0.876) and C-reactive protein (Area under curve: 0.717, Confidence interval: 0.628-0.8.7) in predicting the severity of acute pancreatitis. The best cut-off value of serum procalcitonin to predict severe acute pancreatitis was 0.9 ng/ml with 92.6% sensitivity, 80.3% specificity. The accuracy of serum procalcitonin (85.6%) was better than computed tomography severity index score (73.6 %), Ranson's score (76.8%) and C-reactive protein (64.8%). Conclusion Multifactorial scoring systems are complex and hard to use in clinical basis. Serum procalcitonin can be used as a promising single biomarker, easily done in all setup with better accuracy. And it is comparable to computed tomography severity index and Ranson's scores in earlier prediction of severity of acute pancreatitis.

Laparoscopic Appendectomy Versus Open Appendectomy for Acute Appendicitis: A Prospective Comparative Study

Background Appendicitis is the most common cause for acute abdominal pain. Laparoscopic appendectomy is an effective alternative to open appendectomy. It is a minimally invasive results in less postoperative pain, less wound infection, early return to normal work and less morbidity compared to open appendectomy. Both surgical methods are safe but there has been a controversy about which surgical procedure is the most appropriate. Objective To compare the outcomes of laparoscopic versus open appendectomy. Method In this prospective study, from January 2015 to April 2016, 212 cases of acute appendicitis were included. Diagnosis was based on Alvarado score of seven or above. Patients were distributed into two groups where every alternate patient was operated either open or laparoscopically. The groups were compared in terms of operative time, postoperative pain, postoperative wound infection, other morbidities and length of hospital stay. Result Of 212 patients, 106 underwent open and 104 underwent laparoscopic appendectomy. Other two patients, in whom laparoscopy was converted to open procedure, were excluded from the study. The mean operating time in laparoscopic appendectomy group was 44.57 ± 6.68 minutes and in open appendectomy group, was 36.34 ± 7.47 minutes (p < 0.05). The visual analog scale scores at 6th, 12th, 24th and 48th hours were higher in open appendectomy group compared to laparoscopic appendectomy group (p< 0.05). The hospital stay was 2.63 ± 0.60 days in laparoscopic appendectomy group and 3.26 ± 0.68 days in open appendectomy group (p < 0.05). Surgical site infection in laparoscopic appendectomy and open appendectomy group were 3.8% and 14 % respectively (p< 0.05). Conclusion In laparoscopic appendectomy group, there is lower incidence of wound infection, lesser postoperative analgesic requirement and shorter hospital stay in comparison to open appendectomy. Though, the operative time is more with laparoscopic appendectomy, it can be considered as the gold standard for surgical treatment of acute appendicitis.

The phenotypic spectrum of organic acidurias and urea cycle disorders. Part 1: the initial presentation

BACKGROUND

The clinical presentation of patients with organic acidurias (OAD) and urea cycle disorders (UCD) is variable; symptoms are often non-specific.

AIMS/METHODS

To improve the knowledge about OAD and UCD the E-IMD consortium established a web-based patient registry.

RESULTS

We registered 795 patients with OAD (n = 452) and UCD (n = 343), with ornithine transcarbamylase (OTC) deficiency (n = 196), glutaric aciduria type 1 (GA1; n = 150) and methylmalonic aciduria (MMA; n = 149) being the most frequent diseases. Overall, 548 patients (69 %) were symptomatic. The majority of them (n = 463) presented with acute metabolic crisis during (n = 220) or after the newborn period (n = 243) frequently demonstrating impaired consciousness, vomiting and/or muscular hypotonia. Neonatal onset of symptoms was most frequent in argininosuccinic synthetase and lyase deficiency and carbamylphosphate 1 synthetase deficiency, unexpectedly low in male OTC deficiency, and least frequently in GA1 and female OTC deficiency. For patients with MMA, propionic aciduria (PA) and OTC deficiency (male and female), hyperammonemia was more severe in metabolic crises during than after the newborn period, whereas metabolic acidosis tended to be more severe in MMA and PA patients with late onset of symptoms. Symptomatic patients without metabolic crises (n = 94) often presented with a movement disorder, mental retardation, epilepsy and psychiatric disorders (the latter in UCD only).

CONCLUSIONS

The initial presentation varies widely in OAD and UCD patients. This is a challenge for rapid diagnosis and early start of treatment. Patients with a sepsis-like neonatal crisis and those with late-onset of symptoms are both at risk of delayed or missed diagnosis.

The phenotypic spectrum of organic acidurias and urea cycle disorders. Part 2: the evolving clinical phenotype

BACKGROUND

The disease course and long-term outcome of patients with organic acidurias (OAD) and urea cycle disorders (UCD) are incompletely understood.

AIMS

To evaluate the complex clinical phenotype of OAD and UCD patients at different ages.

RESULTS

Acquired microcephaly and movement disorders were common in OAD and UCD highlighting that the brain is the major organ involved in these diseases. Cardiomyopathy [methylmalonic (MMA) and propionic aciduria (PA)], prolonged QTc interval (PA), optic nerve atrophy [MMA, isovaleric aciduria (IVA)], pancytopenia (PA), and macrocephaly [glutaric aciduria type 1 (GA1)] were exclusively found in OAD patients, whereas hepatic involvement was more frequent in UCD patients, in particular in argininosuccinate lyase (ASL) deficiency. Chronic renal failure was often found in MMA, with highest frequency in mut(0) patients. Unexpectedly, chronic renal failure was also observed in adolescent and adult patients with GA1 and ASL deficiency. It had a similar frequency in patients with or without a movement disorder suggesting different pathophysiology. Thirteen patients (classic OAD: 3, UCD: 10) died during the study interval, ten of them during the initial metabolic crisis in the newborn period. Male patients with late-onset ornithine transcarbamylase deficiency were presumably overrepresented in the study population.

CONCLUSIONS

Neurologic impairment is common in OAD and UCD, whereas the involvement of other organs (heart, liver, kidneys, eyes) follows a disease-specific pattern. The identification of unexpected chronic renal failure in GA1 and ASL deficiency emphasizes the importance of a systematic follow-up in patients with rare diseases.

Diagnostic serum glycosylation profile in patients with intellectual disability as a result of MAN1B1 deficiency

Congenital disorders of glycosylation comprise a group of genetic defects with a high frequency of intellectual disability, caused by deficient glycosylation of proteins and lipids. The molecular basis of the majority of the congenital disorders of glycosylation type I subtypes, localized in the cytosol and endoplasmic reticulum, has been solved. However, elucidation of causative genes for defective Golgi glycosylation (congenital disorders of glycosylation type II) remains challenging because of a lack of sufficiently specific diagnostic serum methods. In a single patient with intellectual disability, whole-exome sequencing revealed MAN1B1 as congenital disorder of glycosylation type II candidate gene. A novel mass spectrometry method was applied for high-resolution glycoprofiling of intact plasma transferrin. A highly characteristic glycosylation signature was observed with hybrid type N-glycans, in agreement with deficient mannosidase activity. The speed and robustness of the method allowed subsequent screening in a cohort of 100 patients with congenital disorder of glycosylation type II, which revealed the characteristic glycosylation profile of MAN1B1-congenital disorder of glycosylation in 11 additional patients. Abnormal hybrid type N-glycans were also observed in the glycoprofiles of total serum proteins, of enriched immunoglobulins and of alpha1-antitrypsin in variable amounts. Sanger sequencing revealed MAN1B1 mutations in all patients, including severe truncating mutations and amino acid substitutions in the alpha-mannosidase catalytic site. Clinically, this group of patients was characterized by intellectual disability and delayed motor and speech development. In addition, variable dysmorphic features were noted, with truncal obesity and macrocephaly in ∼65% of patients. In summary, MAN1B1 deficiency appeared to be a frequent cause in our cohort of patients with unsolved congenital disorder of glycosylation type II. Our method for analysis of intact transferrin provides a rapid test to detect MAN1B1-deficient patients within congenital disorder of glycosylation type II cohorts and can be used as efficient diagnostic method to identify MAN1B1-deficient patients in intellectual disability cohorts. In addition, it provides a functional confirmation of MAN1B1 mutations as identified by next-generation sequencing in individuals with intellectual disability.

Etiology and outcome of inborn errors of metabolism

OBJECTIVES

To study the clinical presentation, diagnostic workup and outcome of children presenting with suspected inborn errors of metabolism.

METHODS

The cross-sectional study was conducted at the Shifa International Hospital, Islamabad, and included all patients diagnosed with the condition between January 2006 and June 2011. Medical records of the patients were reviewed to collect the relevant data.

RESULTS

A total of 10 patients underwent diagnostic work-up. Majority 7 (70%) were males and 6 (60%) presented in the neonatal age group. Seizures and coma were the commonest presentations (n = 5; 50% each) followed by breathing difficulty (n = 4; 40%) and vomiting (n = 2; 20%). The commonest diagnoses were methyl malonic acidaemia (n=2; 20%), non-ketotic hyperglycinaemia (n=7; 10%), fructose 1,6 diphosphatase deficiency (n = 1; 10%), and biotinidase deficiency (n = 1; 10%). Mortality was high (n = 5; 50%) and half of the survivors had severe neurological impairment.

CONCLUSION

The diagnosis of inborn errors of metabolism requires a high index of suspicion. These disorders have a high mortality and risk of long-term neurological disability.

Clinical, biochemical, and molecular studies in pyridoxine-dependent epilepsy. Antisense therapy as possible new therapeutic option

PURPOSE

Pyridoxine-dependent epilepsy seizure (PDE; OMIM 266100) is a disorder associated with severe seizures that can be controlled pharmacologically with pyridoxine. In the majority of patients with PDE, the disorder is caused by the deficient activity of the enzyme α-aminoadipic semialdehyde dehydrogenase (antiquitin protein), which is encoded by the ALDH7A1 gene. The aim of this work was the clinical, biochemical, and genetic analysis of 12 unrelated patients, mostly from Spain, in an attempt to provide further valuable data regarding the wide clinical, biochemical, and genetic spectrum of the disease.

METHODS

The disease was confirmed based on the presence of α-aminoadipic semialdehyde (α-AASA) in urine measured by liquid chromatography tandem mass spectrometry (LC-MS/MS) and pipecolic acid (PA) in plasma and/or cerebrospinal fluid (CSF) measured by high performance liquid chromatography (HPLC)/MS/MS and by sequencing analysis of messenger RNA (mRNA) and genomic DNA of ALDH7A1.

KEY FINDINGS

Most of the patients had seizures in the neonatal period, but they responded to vitamin B6 administration. Three patients developed late-onset seizures, and most patients showed mild-to-moderate postnatal developmental delay. All patients had elevated PA and α-AASA levels, even those who had undergone pyridoxine treatment for several years. The clinical spectrum of our patients is not limited to seizures but many of them show associated neurologic dysfunctions such as muscle tone alterations, irritability, and psychomotor retardation. The mutational spectrum of the present patients included 12 mutations, five already reported (c.500A>G, c.919C>T, c.1429G>C c.1217_1218delAT, and c.1482-1G>T) and seven novel sequence changes (c.75C>T, c.319G>T, c.554_555delAA, c.757C>T, c.787 + 1G>T, c.1474T>C, c.1093-?_1620+?). Only one mutation, p.G477R (c.1429G>C), was recurrent; this was detected in four different alleles. Transcriptional profile analysis of one patient's lymphoblasts and ex vivo splicing analysis showed the silent nucleotide change c.75C>T to be a novel splicing mutation creating a new donor splice site inside exon 1. Antisense therapy of the aberrant mRNA splicing in a lymphoblast cell line harboring mutation c.75C>T was successful.

SIGNIFICANCE

The present results broaden our knowledge of PDE, provide information regarding the genetic background of PDE in Spain, afford data of use when making molecular-based prenatal diagnosis, and provide a cellular proof-of concept for antisense therapy application.

The identification of novel mutations in the biotinidase gene using denaturing high pressure liquid chromatography (dHPLC)

Biotinidase deficiency (BD) is an autosomal recessive disorder of biotin metabolism that causes incomplete recycling of free biotin. The resulting depletion of intracellular biotin leads to impaired activities of biotin-dependent carboxylases. The ensuing clinical phenotype includes progressive neurologic deterioration with epileptic seizures, muscular hypotonia as well as skin eczema. BD may be readily diagnosed by analysing enzyme activity in dried blood spots during newborn screening but typically requires molecular confirmation. More than 100 different mutations in the biotinidase gene have been reported to date. To simplify molecular testing we have developed a rapid and accurate denaturing high pressure liquid chromatography (dHPLC) method of the promoter, 3'UTR, all exons including exon/intron boundaries as a first line screen followed by direct sequencing of the respective PCR products. To validate this method we used DNA from 23 different, newly diagnosed patients with biochemically proven BD from Austria, India, Morocco and Spain. A total of 11 mutations, missense 7, frameshift 3 and 1 nonsense, were screened. Six mutations were novel to this study. All mutations revealed distinct dHPLC pattern thus enabling their accurate detection. This study revealed that dHPLC method is robust, automated, economical and above all highly sensitive for the molecular analysis of biotinidase gene and should be used as a pre-analytical tool followed by sequencing of aberrant heteroduplex forming amplicons.

Manifestation of hawkinsinuria in a patient compound heterozygous for hawkinsinuria and tyrosinemia III

Mutations in the gene for 4-hydroxyphenylpyruvic acid dioxygenase (HPD) cause either autosomal recessive tyrosinemia type III or autosomal dominant hawkinsinuria. We report a 6-month-old Indian infant who is compound heterozygous for both alleles and who has hawkinsinuria but not tyrosinemia type III based on biochemical investigations. The HPD gene was directly sequenced in the proband and both parents. The mechanistic model of the enzymatic function was built using the known structure of rat HPD. We identified a novel hawkinsinuria mutation, Asn241Ser, and a known tyrosinemia type III mutation, Ile335Met, in trans configuration. The structural analysis of the active site revealed that the IIe335Met mutation is situated in the close vicinity of one of the two highly conserved Phe rings which stack with the phenol ring of the substrate. The Asn241Ser mutation is situated further away from the 4-hydroxyphenylpyruvate binding pocket. Assuming that Asn241Ser causes hawkinsinuria, we propose positioning the dioxygen molecule in the HPD-catalyzed reaction as a novel role for the Asn residue. The IIe335Met allele is equivalent to a null mutation while the Asn241Ser allele results in a partially active enzyme with an uncoupled turnover causing hawkinsinuria.