HYPOGLYCEMIA
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Transcript of HYPOGLYCEMIA
HYPOGLYCEMIA
MISSY HORNACC# 165211
Missy Horn• Acc#164629
• 6 year old FS Labrador Retriever
• Presented for progressive generalized weakness and muscle atrophy for 1 year
• BW done in January by rDVM: WNL
Physical Exam Frequently sits/lays down during exam
Mild palmigrade/plantigrade stance
Mild weakness/decreased control and precision when placing paws with each limb advancement
Generalized muscle atrophy; most pronounced over epaxials and pelvic limbs
Neurolocalization: neuromuscular
Bloodwork Performed prior to performing EMG Big 4:
PCV 50% TS 8.0 BUN normal Blood glucose: 38 Insulin levels: Pending
CBC normal
EMG Spontaneous activity noted on multiple
muscles with greatest severity in distal limbs
Slow/abnormal NCV ~41m/s
Consistent with a peripheral neuropathy
Causes of Hypoglycemia Excess insulin secretion or insulin-like factors
Insulinoma, extrapancreatic tumors and islet cell hyperplasia
Dec glucose production Addisons, hypopituitarism, GH deficiency, liver dz,
glycogen storage dzs, neonates, and toy breeds Excess glucose consumption
Sepsis, extreme exercise Drugs
Insulin, oral hypoglycemics, salicylates, acetaminophen, beta blockers, TCAs, ACE -, tetracycline
Spurious
Paraneoplasitc tumors Several tumors can cause a paraneoplastic
syndrome with the production of insulin like growth factor type II Causes hypoglycemia Mesenchymal tumors more common than epithelial Leiomyosarcoma and leiomyoma of the GI tract are
the most frequent mesenchymal tumor Splenic hemangiosarcoma has also been described
Epithelial tumors most commonly from hepatocellular carcinoma
Sporadic cases of oral melanoma and salivary adenocarcinoma have been reported
Insulinoma Diagnosis:
Repeated hypoglycemia: BG < 60 Insulin > 20 Histopathology of a pancreatic mass/nodule
Clinical Signs: Mean age: 9 years Seizures, collapse, weakness, ataxia, disorientation, mental
dullness, and visual disturbances Imaging:
Ultrasonography sensitivity of 56% in dogs and abdominal metastasis identified in 20%
CT: Sensitivity of 71% using conventional pre- and postcontrast CT. sensitivity not determined for dual phase CT angiography but is used for humans
Pathophysiology Insulin secreting tumor of the pancreatic
beta cells Carcinomas account of 60%, with the
remainder being adenomas Are rare but insulinoma is the most
common pancreatic endocrine tumor (insulinoma, gastrinoma, and glucagonoma)
Large breed dogs most affected(Irish Setters, Boxers, and GSDs) but any breed can be affected
Islets of Langerhans: island of endocrine tissue in the otherwise exocrine pancreas
1. Alpha cells: produce glucagon
Acts to inc BG
2. Beta cells: produce insulinActs to dec BG and allows for uptake of glucose into cells
3. Delta cells: produce somatostatinInhibits insulin and glucagon
4. Pancreatic polypeptideInhibits both endocrine and exocrine pancreatic secretions
Treatment Planning Determine if mass is present and/or
resectable If surgically excisable increases life
span Large percentage of animals has
metastasis at time of diagnosis Removal or mass will still increase prognosis
Median survival time of 12-14 months with partial pancreactomy
Young dogs have a worse prognosis
CT characteristics Precontrast: typically iso to hypoattenuating
to adjacent parenchyma Arterial phase: contrast enhancing(peak
enhancement) Venous: less contrast enhancing but still
hyperattenuating compared to adjacent parenchyma
Delay phase: iso to hypoattenuating Insulinomas are highly vascular making
sense why they have peak enhancement during the arterial phase
CT characteristics CT angiography is not 100% sensitive in
detecting insulinomas, likely depending on the vascular supply and size of the tumor
CT angiography is more sensitive than other imaging modalities and is also more sensitive in detecting metastatic disease
If hypoglycemic and elevated insulin levels, surgical exporatory with histopathology is still needed for diagnosis
Hepatic LN
Hepatic Lymph Node
Right Lobe of Pancreas
Pancreatic Mass
Contrast enhancing mass in the left lobe of the pancreas
Acc#15110110yr MC Boxer
Missy If insulin levels are elevated owners will
likely go ahead with abdominal exploratory
In the mean time are feeding small meals frequently and giving prednisone
Prednisone antagonizes the effect of insulin by causing insulin resistance at the level of the insulin receptors
References1. Robben JH, Pollak YW, Kirpensteijn J, et al. Comparison of ultrasonography,computed tomography, and single-photon emission computed tomography for the detection and localization of canine insulinoma. J Vet Intern Med 2005;19:15–22.
2. Mai W, Caceres A. Dual-Phase Computed Tomographic Angiography in Three Dogs With Pancreatic Insulinoma. VRUS(2008) 49; 2: p141-148
3. Ettinger S and Feldman, E. Textbook of Veterinary Internal Medicine: Sixth Edition. 2005 Elsevier Saunders: p1560-1563
4. Zini E, Glaus TM, Minuto F, Arvigo M, Hauser B, Reusch CE. Paraneoplastic hypoglycemia due to an insulin-like growth factor type-II secreting hepatocellular carcinoma in a dog. J Vet Intern Med 2007. Jane-Feb; 21(1): 193-5