Duvoglustat HCl Increases Systemic and Tissue Exposure of Active Acid α-Glucosidase in Pompe Patients Co-administered with Alglucosidase α.

Duvoglustat HCl (AT2220, 1-deoxynojirimycin) is an investigational pharmacological chaperone for the treatment of acid α-glucosidase (GAA) deficiency, which leads to the lysosomal storage disorder Pompe disease, which is characterized by progressive accumulation of lysosomal glycogen primarily in heart and skeletal muscles. The current standard of care is enzyme replacement therapy with recombinant human GAA (alglucosidase alfa [AA], Genzyme). Based on preclinical data, oral co-administration of duvoglustat HCl with AA increases exposure of active levels in plasma and skeletal muscles, leading to greater substrate reduction in muscle. This phase 2a study consisted of an open-label, fixed-treatment sequence that evaluated the effect of single oral doses of 50 mg, 100 mg, 250 mg, or 600 mg duvoglustat HCl on the pharmacokinetics and tissue levels of intravenously infused AA (20 mg/kg) in Pompe patients. AA alone resulted in increases in total GAA activity and protein in plasma compared to baseline. Following co-administration with duvoglustat HCl, total GAA activity and protein in plasma were further increased 1.2- to 2.8-fold compared to AA alone in all 25 Pompe patients; importantly, muscle GAA activity was increased for all co-administration treatments from day 3 biopsy specimens. No duvoglustat-related adverse events or drug-related tolerability issues were identified.

An incidental case of dihydropyrimidine dehydrogenase deficiency: One case, multiple challenges.

Dihydropyrimidine dehydrogenase (DPD) deficiency is an autosomal recessive disorder that shows large phenotypical variability, ranging from no symptoms to intellectual disability, motor retardation, and convulsions. In addition, homozygous and heterozygous mutation carriers can develop severe 5-fluorouracil (5-FU) toxicity. The lack of genotype-phenotype correlation and the possibility of other factors playing a role in the manifestation of the neurological abnormalities, make the management and education of asymptomatic DPD individuals more challenging. We describe a 3-month-old baby who was incidentally found by urine organic acid testing (done as part of positive newborn screen) to have very high level of thymine and uracil, consistent with DPD deficiency. Since the prevalence of asymptomatic DPD deficiency in the general population is fairly significant (1 in 10,000), we emphasize in this case study the importance of developing a guideline in genetic counseling and patient education for this condition as well as other incidental laboratory findings.

A Non-classical Presentation of Tangier Disease with Three ABCA1 Mutations.

Tangier disease is a very rare autosomal recessive inherited disorder characterized by markedly reduced high-density lipoprotein (HDL) levels, characteristic large, yellow-orange tonsils, and enlarged liver, spleen and lymph nodes. It is caused by mutations in the ABCA1 gene. There is no specific treatment, and medications traditionally used to increase HDL are ineffective. A number of patients with non-classical Tangier disease have been described in the literature, who presented with low HDL levels, corneal lesions, hepatosplenomegaly, and thrombocytopenia. We report here about a 45-year-old female with a past medical history of early coronary artery disease, myocardial infarction, multiple episodes of angina, immeasurable HDL, and a history of idiopathic thrombocytopenia purpura. She had a tonsillectomy performed previously, but did not remember if the tonsils were of any unusual color. There was no history of peripheral neuropathy. Her family history is significant for her father and mother having Alzheimer disease and hypertension, respectively. On physical examination she did not have any hepatosplenomegaly or corneal opacities. She was found to have three mutations in the ABCA1 gene. These were designated A1046D (c.3137C>A) in exon 22; Y1532C (c.4595A>G) in exon 34, and W1699C (c.5097G>T) in exon 37. All three have been reported to be deleterious in functional studies. The patient has immeasurable HDL, which leads us to assume that two mutations are on one allele and one mutation on the other. We suspect that this condition is under-diagnosed, and as more patients are reported in the literature, the phenotype of Tangier disease will be elucidated further.

MCT oil-based diet reverses hypertrophic cardiomyopathy in a patient with very long chain acyl-coA dehydrogenase deficiency.

Very long chain acyl-CoA dehydrogenase (VLCAD) deficiency is one of the genetic defects of mitochondrial fatty acid beta-oxidation presenting in early infancy or childhood. If undiagnosed and untreated, VLCAD deficiency may be fatal, secondary to cardiac involvement. We assessed the effect of replacing part of the fat in the diet of a 2 ½-month-old male infant, who was diagnosed with VLCAD deficiency,with medium-chain triglyceride (MCT) oil and essential fats. The patient presented with vomiting, dehydration, and was found to have persistent elevation of liver function tests, hepatomegaly, pericardial and pleural effusion, right bundle branch block, and biventricular hypertrophy. Because of the cardiomyopathy, hepatomegaly, and an abnormal acylcarnitine profile and urine organic acids, he was suspected of having VLCAD deficiency. This was confirmed on acyl-coA dehydrogenase, very long chain (ACADVL) gene analysis. He was begun on an MCT oil-based formula with added essential fatty acids, uncooked cornstarch (around 1 year of age), and frequent feeds. By 7 months of age, cardiomyopathy had reversed and by 18 months of age, all cardiac medications were discontinued and hypotonia had improved such that physical therapy was no longer required. At 5 years of age, he is at the 50(th) percentile for height and weight along with normal development. Pediatricians need to be aware about the basic pathophysiology of the disease and the rationale behind its treatment as more patients are being diagnosed because of expansion of newborn screen. The use of MCT oil as a medical intervention for treatment of VLCAD deficiency remains controversial mostly because of lack of clear phenotype-genotype correlations, secondary to the genetic heterogeneity of the mutations. Our case demonstrated the medical necessity of MCT oil-based nutritional intervention and the need for the further research for the development of specific guidelines to improve the care of these patients.

Papillary thyroid cancer in a patient with MUTYH-associated polyposis (MAP).

We describe a patient with MUTYH-associated polyposis diagnosed with colon cancer at 33 years of age, as well as gastric polyps at a later age. She was also diagnosed with papillary thyroid cancer at age 35. MUTYH-associated polyposis is an autosomal recessively inherited disease which has clinical overlap with Familial adenomatous polyposis and its attenuated form, in that it is associated with risk of colon cancer at a young age. Extra-intestinal cancers have also been reported in patients with MUTYH-associated polyposis; however the tumor spectrum is still evolving. National Comprehensive Cancer Network guidelines recommend screening for colon, duodenal and gastric polyps in individuals with MUTYH-associated polyposis. Screening for extra-intestinal cancers i.e. thyroid cancer is presently not part of these recommendations. These will likely continue to evolve as the MUTYH-associated polyposis tumor spectrum is better understood as a result of future case reports and research.

Assessment of hepatitis B vaccination status in doctors of services hospital, Lahore.

BACKGROUND: Hepatitis B is the most common serious infection of the liver and can lead to premature death from liver cancer or liver failure. Of the two billion people who have been infected with Hepatitis B virus, more than 350 million have chronic infection. The objectives of this study were to assess the Hepatitis B vaccination status, reasons for non-compliance and the risk of exposure to doctors at a tertiary care hospital. METHODS: Three hundred and twenty-two doctors were selected from the various departments of the hospital by simple random sampling. They were given a self-administered questionnaire after taking verbal consent. Some doctors refused to fill-in the questionnaire while some others were on leave during the time of study and the remaining 215 doctors responded to the questionnaire. RESULTS: A total of 215 doctors, (age range 22-59 years) responded to the questionnaire. Amongst them 11.6% had not received even a single dose of Hepatitis B vaccine while 14.4% had not completed the required course of vaccination. Most common reason cited by doctors for non-immunisation was that they had not thought about it. Consultants were more likely of the other doctors to have received completed vaccination (83.9% versus 69.9%) (p<0.05). They were also significantly more likely to know their antibody titre after completing vaccination. Needle stick injuries were common. One hundred and forty-five doctors in the study admitted having received at least one needle prick/sharp injury. Of them, 51.6% had received a needle prick/sharp injury more than once. CONCLUSION: Despite the availability of an effective vaccine in the market doctors continue to remain non-vaccinated. It is the lack of awareness and carelessness on part of doctors coupled with the negligence of the risk that has led them being incompletely vaccinated. There is a need to ensure that every doctor is completely vaccinated against Hepatitis B before he/she enters professional practice.