G lycogen storage disease (GSD) type I is an autosomal recessive disorder of glycogen metabolism that affects 1 in 100,000 live births (1). The disorder is caused by mutations in genes that encode for glucose-6-phosphatase (type Ia) and glucose-6-phosphate (G6P) translocase (type Ib) (2). Complications of GSD are difficulty maintaining glucose homeostasis, renal disease, hepatic adenomas, hypertriglyceridemia, hyperlactatemia, and hyperuricemia. Neutrophil dysfunction, in GSD Ib, differentiates the subtypes.Since the mid-1970s, reports have linked the defect in glucose-6-phosphate translocase function with inflammatory bowel disease (IBD). In 1978, Narisawa et al (3) described IBD in 1 patient with GSD I, but subtyping was not available. Other case reports followed, but have been in reference to the GSD Ib population. Impaired neutrophil function is the proposed cause for the development of IBD in that population (4).Visser et al ( 5) reported worsening diarrhea in patients with GSD I of both subtypes; however, the mechanism in patients with GSD Ia remains unexplained. In a previous study, 18 patients with GSD Ia with diarrhea were evaluated with colonoscopy and fecal a-1-antitrypsin, with nonspecific colonic inflammation noted on histology and a-1-antitrypsin within normal limits (5). Presently, a characterization of IBD in genetically proven GSD Ia does not exist.

Most patients with glycogen storage disease (GSD) type Ib show features related to inflammatory bowel disease (IBD). The development of IBD seems to be associated with the defect of neutrophil function in GSD Ib. Patients with GSD Ia were not recognized to have similar gastrointestinal complaints until recently and are not associated with a neutrophil defect. Fifty consecutive GSD Ia inpatients over the age of 2 years without a diagnosis of IBD were screened using serologic and genetic markers via the Prometheus IBD sgi Diagnostic test. Eleven patients were tested positive for IBD (22%), with five fitting the pattern for Crohn's disease, five for ulcerative colitis, and one with nonspecific IBD. Only 2 out of the 11 patients had any gastrointestinal complaints. No pattern could be distinguished from individual inflammatory markers, genetics, inflammation antibodies, age, complications, or metabolic control. Of note, 9 out of 11 patients testing positive were female. Patients with GSD Ia were found to have a higher rate of serologically indicated IBD when compared with the general population. While these subjects will need to be followed to determine if these serologic markers correlate with clinical disease, this study supports that IBD may be more common in the GSD Ia population. Further studies are warranted to explain the relationship between IBD and GSD I since it may provide clues regarding the pathogenesis of IBD development in the general population.

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7526 Background: The presence of deletion 17p (del17), determined by chromosome analysis and/or fluorescence in situ hybridization (FISH), is a strong negative prognostic marker in chronic lymphocytic leukemia (CLL). Prior to the introduction of novel agents (ibrutinib, venetoclax), the clinical utility of cytogenetics/FISH was limited by the absence of chemoimmunotherapy regimens that were proven effective in patients with del17. Testing practices for chromosomal aberrations since the introduction of novel agents have not been reported. We report cytogenetic/FISH trends in a nationwide cohort of veterans diagnosed with CLL. Methods: CLL patients diagnosed 2008-2015 and receiving care at VA were identified through the VA Clinical Cancer Registry. Electronic medical records were used to determine cytogenetic/FISH testing (lab records), treatment histories (pharmacy dispensation records), and evidence of system use (heme-onc notes). Cytogenetic/FISH testing was identified by presence of specific keywords in the test name or Logical Observation Identifiers Names and Codes (LOINC) descriptions, then validated by human annotation. The testing rates are reported for the entire cohort, at time of diagnosis, time of regimen initiation (including the 12 months preceding initiation), during the novel era (2014 – 2015) and prior (2008–2013). Results: From 2008 to 2015, 3,638 CLL patients were diagnosed and received care at VA. Documented records of treatment regimens were available for 1,562 patients who received a total of 2,929 treatment regimens. Only 24% (998) of patients were tested at any point in time during their care at the VA, 17% (622) were tested at time of diagnosis, and 19% (542) of treatment courses were preceded by cytogenetic/FISH testing. No testing differences existed following the introduction of the novel agents at diagnosis (both ~ 17%), or prior to regimen initiation (20% vs 16%). Conclusions: Our study suggests CLL patients diagnosed and receiving care at the VA are not routinely undergoing cytogenetics/FISH testing at diagnosis or prior to treatment. Changing this practice pattern will personalize treatments so that del17 CLL patients receive less toxic and more effective therapies.