Biocompatible Supramolecular Mesoporous Silica Nanoparticles as the Next-Generation Drug Delivery System

Supramolecular mesoporous silica nanoparticles (MSNs) offer distinct properties as opposed to micron-sized silica particles in terms of their crystal structure, morphology–porosity, toxicity, biological effects, and others. MSN biocompatibility has touched the pharmaceutical realm to exploit its robust synthesis pathway for delivery of various therapeutic molecules including macromolecules and small-molecule drugs. This article provides a brief review of MSN history followed by special emphasis on the influencing factors affecting morphology–porosity characteristics. Its applications as the next-generation drug delivery system (NGDDS) particularly in a controlled release dosage form via an oral drug delivery system are also presented and shall be highlighted as oral delivery is the most convenient route of drug administration with the economical cost of development through to scale-up for clinical trials and market launch.

787 The Hidden and The Lost: A Case of a Rare Complication from A Long-Lost Surgical Technique

Background

Various operative techniques have been developed for liver transplant since the 1960's. Waddell-Calne technique for biliary reconstruction in orthotopic liver transplant (OLT) was one of the rare and now relatively obsolete techniques. The aim of our presentation is to describe a long-term complication of this lost technique and how it posed multiple diagnosis and management challenges after 35 years post-liver transplant.

Case presentation

Our case is on a 50-year-old lady with a history of OLT for end-stage liver failure secondary to type-1 autoimmune hepatitis. Peri and postoperative period were completely unremarkable. 35 years later, she presented with symptoms of recurrent cholangitis. Magnetic resonance cholangio-pancreaticography demonstrated biliary tree dilatation with choledocholithiasis and possible cholecystitis. Removal of the distal stones together with pig-tail stent insertion was achieved via endoscopic retrograde cholangio-pancreaticography, however, her biliary colic persisted. The background of OLT and grossly distorted anatomy on imaging posed a challenge for further surgery. Extensive tracing of the history back from 1985 and multicentre multidisciplinary discussion revealed that the Waddell-Calne technique was carried out for her OLT where a gallbladder conduit was used for the hepaticojejunal-anastomosis. Finally, excision of the gallbladder conduit and hepaticojejunostomy with long Roux-en-Y was able to perform successfully.

Conclusions

Waddle-Calne technique is rarely seen globally nowadays but should be considered as a possible cause of recurrent cholangitis in patients with a history of OLT a long time ago. We demonstrated that the knowledge of such a rare procedure, together with the multidisciplinary approach could enormously benefit the management of the case.

794 Diagnostic Pitfall in Atypical Presentation of Malignant Gastric Ulcer Perforation

Background

Peptic ulcer perforation is one of the most common surgical problems in daily practice. Although it can be easily diagnosed clinically, the clinical presentation can be less obvious in some cases leading to diagnostic pitfalls and mortality. This case report aims to highlight an atypical presentation of malignant gastric ulcer perforation in a patient with chronic abdominal pain.

Case presentation

A 78-year-old lady presented with chronic abdominal pain for 3 months. Investigations and imaging revealed T2N1M0 malignant gastric ulcer which was confirmed by endoscopy. Due to her low body mass index and underlying comorbidities, she was admitted for pre-operative optimization. However, she was a good 78 with the clinical frailty scale 4 and the National Early Warning Score 0 throughout the stay. On the night before the operation, she suddenly developed delirium. Further history revealed marked oliguria for 12 hours. There was mild abdominal distension without peritonism. She was catheterized and treated with fluids and antibiotics. X-ray suggested massive pneumoperitonium. Subsequently, she developed full-blown septic shock with rapid clinical deterioration within 3 hours. With the estimated Boey scoring of 3 and rapid clinical deterioration, the symptom control approach was decided. A palliative bedside ascitic tap was performed to relieve the discomfort. Four hours after the onset, unfortunately, the patient passed away.

Conclusions

Although gastric ulcer perforation usually presents with obvious symptoms, extra precaution should be exercised in elderly patients with chronic abdominal pain and comorbidities. We could learn that routine monitoring of urine output might aid in the early diagnosis of sepsis.