What are the possible causes of left upper‑quadrant abdominal pain in an adult patient with diabetes who also presents with chest pain?

Causes of Left Upper Quadrant Pain in a Diabetic Patient with Chest Pain

In a diabetic patient presenting with both LUQ pain and chest pain, you must immediately exclude life-threatening cardiac ischemia before attributing symptoms to abdominal pathology, then obtain contrast-enhanced CT abdomen/pelvis to evaluate for splenic infarction (from embolic sources), splenic sequestration, gastric/pancreatic disease, and diabetic ketoacidosis-related abdominal pain. 1, 2

Immediate Cardiac Evaluation

• Coronary artery disease must be ruled out first because it remains the leading cause of death in diabetic patients and can present atypically with LUQ pain rather than classic substernal chest discomfort. 1
• Obtain ECG, troponin, and focused cardiac history emphasizing exertional relationship, duration, and associated symptoms (dyspnea, diaphoresis, nausea). 1
• Women and elderly diabetics are at particularly high risk for atypical presentations and underdiagnosis of acute coronary syndrome. 1
• Pericarditis should be considered as another cardiac cause that can radiate to the LUQ. 2, 3

Splenic Pathology (High-Risk in Diabetics)

Splenic Infarction

• Diabetic patients have increased thrombotic risk from hypercoagulability, microvascular disease, and higher rates of atrial fibrillation, making splenic infarction a critical consideration. 2, 4
• Embolic sources include endocarditis (more common in diabetics with poor glycemic control), atrial fibrillation with cardiac thrombus, and atherosclerotic disease. 2, 5
• Kehr's sign (referred left shoulder pain) is a classic indicator of splenic capsular irritation from infarction or subcapsular hematoma. 2, 4
• Once infarction is confirmed on CT, obtain transthoracic echocardiography to identify embolic sources and initiate anticoagulation when not contraindicated. 4

Splenic Abscess

• Fever with LUQ pain mandates urgent contrast-enhanced CT to evaluate for abscess, which requires early drainage to prevent rupture and peritonitis. 2, 4
• Diabetics are at markedly increased risk for splenic abscess from hematogenous spread (endocarditis), immunocompromise, and superinfection of pre-existing splenic lesions. 2
• CT-guided percutaneous drainage is first-line therapy in hemodynamically stable patients to preserve splenic immune function. 4

Splenic Sequestration/Rupture

• An acute drop in hemoglobin/hematocrit signals splenic sequestration or active bleeding, both life-threatening emergencies requiring immediate vital-sign monitoring. 2, 4
• Any cause of splenomegaly (portal hypertension from diabetic cirrhosis, lymphoproliferative disorders, infectious mononucleosis) markedly increases rupture risk. 2, 3

Pancreatic and Gastric Causes

Pancreatitis

• Diabetics have higher rates of hypertriglyceridemia-induced pancreatitis, which presents with epigastric/LUQ pain radiating to the back. 2, 3
• Contrast-enhanced CT is required to diagnose pancreatitis and detect complications (necrosis, pseudocyst, abscess). 6

Peptic Ulcer Disease and Gastritis

• These are common LUQ pain sources that must be excluded before focusing on primary LUQ pathology. 2, 3
• Diabetics with autonomic neuropathy may have delayed gastric emptying, though upper abdominal symptoms in Type 1 diabetics are often unrelated to gastroparesis severity. 7

Jejunal Diverticulitis

• Though rare (0.3–2% prevalence), jejunal diverticulitis carries 20–25% mortality from perforation, bleeding, and obstruction, and can present with LUQ pain radiating to the left iliac fossa. 8
• Diabetics are at higher risk for diverticular complications; CT with IV contrast is diagnostic. 8

Diabetic Ketoacidosis-Related Abdominal Pain

• Abdominal pain occurs in 46% of DKA patients and is strongly associated with severe metabolic acidosis (bicarbonate <10 mmol/L, pH <7.2), not hyperglycemia severity. 9
• Check serum glucose, bicarbonate, pH, and ketones in any diabetic with acute abdominal pain and chest discomfort (which may reflect Kussmaul respirations). 9
• Abdominal pain from DKA typically resolves with correction of acidosis; persistent pain after metabolic stabilization mandates imaging to exclude surgical pathology. 9
• Diabetics with alcohol or cocaine abuse have higher rates of DKA-associated abdominal pain. 9

Renal and Urologic Causes

• Pyelonephritis and renal colic can mimic LUQ pain and are more common in diabetics due to increased urinary tract infection risk. 2, 3
• Contrast-enhanced CT detects renal stones, pyelonephritis, and perinephric abscess. 6

Pulmonary Causes

• Pneumonia with pleuritic pain can present as LUQ discomfort, especially lower-lobe pneumonia. 3
• Obtain chest X-ray or CT chest if respiratory symptoms (cough, dyspnea, pleuritic pain) are present. 1

Diagnostic Imaging Algorithm

First-Line Study

• Contrast-enhanced CT abdomen/pelvis with IV contrast is the primary imaging modality, providing ~69% sensitivity and excellent specificity for acute LUQ abnormalities. 6, 2
• IV contrast is mandatory because it visualizes splenic parenchyma, detects infarcts (ultrasound misses ~82%), characterizes hematomas/abscesses, and identifies vascular lesions. 2, 4

When to Avoid Non-Contrast CT

• Non-contrast CT markedly reduces detection of splenic infarcts, small lesions, vascular abnormalities, and inflammatory processes (pancreatitis, gastroenteritis, colitis). 6, 2

Role of Ultrasound

• Ultrasound has only ~18% sensitivity for splenic infarction compared with contrast-enhanced CT and should not be the primary modality. 2, 4
• Ultrasound may be used for initial screening of splenic size and serial monitoring in stable patients, but must not replace CT when acute pathology is suspected. 6, 4

Alternative Modalities

• MRI (with and without IV contrast) achieves 96–99% diagnostic accuracy and is preferred for pregnant patients or children when available, though limited by acute-setting availability. 6, 2

Critical Pitfalls to Avoid

• Do not rely on physical examination alone; LUQ examination has the lowest inter-rater reliability among abdominal quadrants (<5% of abdominal pain truly localizes there), especially in elderly diabetics who may provide unreliable histories. 2, 4
• Do not delay imaging based on "reassuring" vital signs or exam; splenic infarction, early abscess, and DKA-related pain can be afebrile and hemodynamically stable initially. 2, 4
• Absence of fever does not exclude serious splenic pathology (infarction, early abscess formation). 4, 3
• Do not attribute all abdominal pain to DKA without imaging if bicarbonate is >10 mmol/L or if pain persists after acidosis correction. 9
• Avoid routine oral contrast, which delays workflow without diagnostic benefit and may obscure gastrointestinal pathology. 2, 4

Laboratory Workup

• Obtain CBC with differential to detect anemia (splenic sequestration/bleeding), leukocytosis (infection/abscess), or thrombocytopenia (hypersplenism). 2, 4
• Check serum glucose, bicarbonate, pH, and ketones to evaluate for DKA. 9
• Measure troponin and obtain ECG to exclude acute coronary syndrome. 1
• Lipase and liver enzymes help identify pancreatitis and hepatobiliary disease. 10
• Urinalysis detects urinary tract infection or hematuria from renal colic. 10