The pancreas is an important organ not only for glucose metabolism but also for lipid metabolism. The pancreas is an elongated leaf-like organ (macam daun kangkong). It has a head section, a mid-section and a tail section. Cancer of the tail section is rare but can occur in adults over 50 years old.
CASE STUDY
Trigger 1
An expatriate middle-aged Cambodian Malay ustaz was on his regular visit to the masjid to teach some religious lessons to the village kids in Kg Chicha, Kelantan. However, the people who go to masjid noticed that he had lost weight and appeared a bit too thin and too pale. He had bouts of diarrhoea. His diabetic status was unknown but he had some rashes. He showed no other symptoms except for tiredness after his duties at the masjid. Worried about the ustaz's deteriorating health, the villagers asked for opinions from their elders and referred him to the nearest hospital.
He was attended to by the A&E doctor, who in turn referred him to the radiologist, endocrinologist, neurologist, pathologist, dermatologist, biochemist and psychiatrist. Blood samples were taken and dispatched to the clinical laboratories. Skin biopsy samples were taken. CT scan of the pancreas was performed. Pancreatic biopsy was ordered.
Trigger 2
Data for the investigations returned the following:
Modified Oral Glucose Tolerance Test (mOGTT): diabetic profile
Serum insulin: reduced
Serum gastrin: ?
Serum vasoactive intestinal peptide (VIP): ?
Liver function test (LFT): low albumin
Serum zinc: reduced
Hemoglobin: 7%
Venous thrombosis (blood clots): +ve
Blood glucagon: 1,000 times higher than normal
Serum amino acids profile: low levels of circulating amino acids
Serum essential fatty acids profile: deficiency of essential fatty acids
Neurological and psychiatric symptoms: +ve
Pancreatic biopsy: alpha-cell tumour (glucagonoma) detected in the tail of the pancreas
Skin: necrolytic migratory erythema
He was diagnosed to be suffering from diabetes mellitus, diarrhoea, weight loss and anaemia due to glucagonoma of the pancreatic tail.
Trigger 3
The ustaz was referred for pancreatic surgery which he underwent successfully at the same hospital. He received prescribed medications and was asked to return in 6 weeks for re-assessment of his health status. He recuperated at home and was visited by the villagers. They noticed he looked and felt much better. After a month's recovery, the ustaz was back at his teaching duties at the masjid.
Back at the hospital, the doctors were happy with the ustaz's speedy recovery. However, they were worried about the prognosis.
Discussion Questions
1. Explain the patient's underlying condition.
Necrolytic migratory erythema is a characteristic rash usually occurring in the glucagonoma syndrome. Glucagonoma syndrome is due to a slow-growing cancerous tumour located in the alpha-cells of the pancreas. Glucagonoma is very rare and affects adults over the age of 50. The tumour secretes excessive amounts of the hormone glucagon.
2. Explain possible causes of the patient's rashes.
It is not known how the rash arises.
(i) It may be due to a relative deficiency of zinc and essential fatty acids because the tumour reduces the amount of albumin that normally carries it around the body.
(ii) Excessive glucagon may increase the amount of inflammation in the skin, particularly in friction sites.
Other medical conditions which may result in a similar rash are:
- Hepatic cirrhosis
- Coeliac disease
- Cystic fibrosis causing intestinal malabsorption
- Nutritional deficiencies of amino acid, zinc, and essential fatty acids
3. Explain how diabetes developed in this patient.
Excessive glucagon also raises the blood glucose, which eventually leads to diabetes mellitus.
4. Explain why the patient experienced weight loss, anaemia and had low levels of amino acids.
Excessive glucagon destroys protein and fat resulting in weight loss, anaemia and low levels of amino acids.
5. Explain the rationale for the investigations.
- Blood count - may reveal anaemia
- Glucose tolerance test - to assess diabetes mellitus
- Liver function - may detect secondary growths in the liver (metastases)
- Serum glucagon levels - may be up to 1000 times normal
- Levels of amino acids - may be very low
- Serum insulin, gastrin, and vasoactive intestinal peptide levels - may reveal other endocrine abnormalities
- Skin biopsy - may reveal inflammation and separation of the superficial layers of the epidermis (necrolytic migratory erythema)
- CT scan - glucagonoma is usually detected in the tail of the pancreas by computed tomography (CT scan), although conventional chest x-ray, magnetic resonance imaging (MRI) and coeliac axis angiography may also be useful.
6. What is the prognosis of the patient's condition?
About 50% of patients die within 5 years of diagnosis.
External link
http://new.dermnetnz.info/systemic/necrolytic-erythema.html
