Research priorities for liver glycogen storage disease: An international priority setting partnership with the James Lind Alliance

The international liver glycogen storage disease (GSD) priority setting partnership (IGSDPSP) was established to identify the top research priorities in this area. The multiphase methodology followed the principles of the James Lind Alliance (JLA) guidebook. An international scoping survey in seven languages was distributed to patients, carers, and healthcare professionals to gather uncertainties, which were consolidated into summary questions. The existing literature was reviewed to ensure that the summary questions had not yet been answered. A second survey asked responders to prioritize these summary questions. A final shortlist of 22 questions was discussed during an international multi-stakeholder workshop, and a consensus was reached on the top 11 priorities using an adapted nominal group technique.In the first survey, a total of 1388 questions were identified from 763 responders from 58 countries. These original uncertainties were refined into 72 summary questions for a second prioritization survey. In total 562 responders from 58 countries answered the second survey. From the second survey, the top 10 for patients, carers and healthcare professionals was identified and this shortlist of 22 questions was taken to the final workshop. During the final workshop, participants identified the worldwide top 11 research priorities for liver GSD. In addition, a top three research priorities per liver GSD subtype was identified.This unique priority setting partnership is the first international, multilingual priority setting partnership focusing on ultra-rare diseases. This process provides a valuable resource for researchers and funding agencies to foster interdisciplinary and transnational research projects with a clear benefit for patients.

Glycogenotic hepatocellular carcinoma with glycogen-ground-glass hepatocytes: A heuristically highly relevant phenotype

Glycogenotic hepatocellular carcinoma (HCC) with glycogen-ground-glass hepatocytes has recently been described as an allegedly “novel variant” of HCC, but neither the historical background nor the heuristic relevance of this observation were put in perspective. In the present contribution, the most important findings in animal models and human beings related to the emergence and further evolution of excessively glycogen storing (glycogenotic) hepatocytes with and without ground glass features during neoplastic development have been summarized. Glycogenotic HCCs with glycogen-ground-glass hepatocytes represent highly differentiated neoplasms which contain subpopulations of cells phenotypically resembling those of certain types of preneoplastic hepatic foci and benign hepatocellular neoplasms. It is questionable whether the occurrence of glycogen-ground-glass hepatocytes in a glycogenotic HCC justifies its classification as a specific entity. The typical appearance of ground-glass hepatocytes is due to a hypertrophy of the smooth endoplasmic reticulum, which is usually associated with an excessive storage of glycogen and frequently also with an expression of the hepatitis B surface antigen. Sequential studies in animal models and observations in humans indicate that glycogen-ground-glass hepatocytes are a facultative, integral part of a characteristic cellular sequence commencing with focal hepatic glycogenosis potentially progressing to benign and malignant neoplasms. During this process highly differentiated glycogenotic cells including ground-glass hepatocytes are gradually transformed via various intermediate stages into poorly differentiated glycogen-poor, basophilic (ribosome-rich) cancer cells. Histochemical, microbiochemical, and molecular biochemical studies on focal hepatic glycogenosis and advanced preneoplastic and neoplastic lesions in tissue sections and laser-dissected specimens in rat and mouse models have provided compelling evidence for an early insulinomimetic effect of oncogenic agents, which is followed by a fundamental metabolic switch from gluconeogenesis towards the pentose-phosphate pathway and the Warburg type of glycolysis during progression from preneoplastic hepatic glycogenosis to the highly proliferative malignant phenotype.

Inherited hyperuricemic disorders

Inherited hyperuricemic disorders fall into two major classes, metabolic overproduction of purines and renal tubular undersecretion. The aim was to explore both. Methodology was a combination of personal experience and review of relevant literature. The overproduction of hyperuricemias result from deficiency of hypoxanthine-guanine phosphoribosyl transferase, overactivity of phosphoribosylpyrophosphate synthetase and deficiency of glucose-6-phosphatase. The undersecretion disorders are autosomal dominantly inherited and are heterogeneous. A major number of these patients result from mutations in the gene that codes for uromodulin. Treatment is with allopurinol.

More questions: 10 years later from glycogen storage disease patient support groups in Europe

In 1990 the first Fulda Workshop on Glycogen Storage Disease (GSD) type I was held in November. Eight adult representatives from Patient groups in the UK, USA, Germany and the Netherlands were invited to come and set up an information table of posters, leaflets etc. We were also asked to present a short list of questions that can occur to parents after the initial shock of diagnosis and treatment of GSD has been made. These "Questions of Parents" were presented on the final day. Ten years later, patient representatives from Europe were invited to present "More Questions: 10 Years Later". On both occasions the questions centred around six broad areas: (1). treatments, (2). specific problems, (3). family planning, (4). long-term effects of having GSD type Ia and Ib, (5). research and (6). general questions.

CONCLUSION

As representatives of GSD support groups, we hope that firm decisions can be agreed for common dietary and pharmacological treatment and follow-up procedures within the boundaries of cultural differences and financial circumstances. We anticipate that if there is a third Fulda workshop in 2010, the answer to the question "Is there a common set of protocols and guidelines among doctors and hospitals as to the correct treatment for glycogen storage disease type I?" will be a firm "Yes".

Glycogen Storage Disease Associated With Left Ventricular Aneurysm in an Elderly Patient

Glycogen storage disease (GSD) types II, III, IV, and V may be associated with cardiomyopathy, but, with the exception of type III GSD, adult cases are extremely rare. A 62-year-old man was found to have GSD and a concomitant left ventricular aneurysm. He had been comparatively well until the age of 62 years, although he had suffered a cerebral infarction at the age of 35 years. The damage caused by glycogen deposition was strictly confined to the myocardium. Left ventriculography revealed a left ventricular aneurysm in the apex. The serial change on electrocardiogram, as well as the findings of the echocardiogram and of cardiac catheterization, resembled those of the dilated phase of hypertrophic cardiomyopathy. However, a left ventricular endomyocardial biopsy specimen revealed central vacuolar degeneration of myocytes with depositions of glycogen. The GSD type remains unknown in the present patient, because the activity of debranching enzyme (type III) measured from the skeletal muscle specimen was normal, whereas that of acid maltase (type II) was slightly low. It is possible that there is a specific malfunction of the acid maltase of the myocardium in the present patient.