After reading this note you will be able to recognise, investigate and manage hypoglycaemia in the Kenyan clinical setting, while remembering to verify drug doses and local protocols against the Kenya MoH guideline and your hospital formulary.
Definition
Hypoglycaemia is a plasma glucose concentration low enough to cause neuro‑glycopenic symptoms or signs. In practice, a capillary glucose < 2.8 mmol/L (≈50 mg/dL) or any level that produces symptoms that resolve with glucose administration is considered clinically significant.
Anatomy and physiology you need
| System | Key element | Clinical relevance |
|---|---|---|
| Pancreas | β‑cell insulin secretion (glucose‑stimulated) | Excess insulin → rapid glucose fall |
| Liver | Glycogenolysis & gluconeogenesis (via glucagon, catecholamines) | Primary source of endogenous glucose during fasting |
| Adrenal medulla | Epinephrine release | Counter‑regulatory hormone, raises glucose |
| Kidney | Gluconeogenesis (especially in prolonged fasting) | Supports glucose homeostasis when liver capacity is exhausted |
| Brain | Glucose‑dependent metabolism | Symptoms arise when cerebral glucose < 2.5 mmol/L |
| Peripheral tissues | GLUT transporters (insulin‑dependent & independent) | Determine glucose uptake rate |
Understanding that insulin drives glucose into muscle and fat, while glucagon, epinephrine, cortisol and growth hormone oppose this, is essential for interpreting why hypoglycaemia occurs in different contexts.
Causes and risk factors
| Category | Common causes in Kenya | Specific risk factors |
|---|---|---|
| Medication‑induced | Sulfonylureas, meglitinides, insulin analogues, high‑dose quinine (rare) | Poor adherence to dosing schedule, renal impairment, concomitant alcohol |
| Endocrine | Insulinoma, adrenal insufficiency, hypopituitarism | Chronic steroid withdrawal, pituitary surgery |
| Critical illness | Severe malaria, disseminated TB, sepsis, HIV/AIDS with opportunistic infections, sickle cell crisis | Malnutrition, hepatic dysfunction, renal failure |
| Nutritional | Prolonged fasting, malnutrition, bariatric surgery | Low carbohydrate intake, night‑time fasting in children |
| Hepatic & renal disease | Advanced cirrhosis, acute hepatitis, chronic kidney disease | Impaired gluconeogenesis, reduced insulin clearance |
| Inborn errors (rare) | Glycogen storage disease, fatty acid oxidation defects | Present in childhood, often missed |
Pathophysiology
- Reduced glucose input → ↓ oral/enteral carbohydrate → ↓ plasma glucose
- Impaired hepatic output → ↓ glycogenolysis & gluconeogenesis (liver disease, sepsis)
- Excess insulin activity → ↑ peripheral uptake + ↓ hepatic glucose production (insulinoma, sulfonylureas)
- Counter‑regulatory failure → inadequate glucagon/epinephrine response (advanced liver disease, autonomic neuropathy)
- Increased peripheral consumption → high metabolic demand (malaria, sickle cell crisis)
Result: Plasma glucose falls below the neuro‑glycopenic threshold → neuronal dysfunction → clinical symptoms.
End of part 1.
Clinical features
| Aspect | Questions to ask | Why it matters / expected finding |
|---|---|---|
| Timing of symptoms | “When did the episode start? How long does it last? Is it related to meals or fasting?” | Hypoglycaemia classically occurs after a prolonged fast (≥ 8 h) or soon after a carbohydrate‑rich meal in insulin‑oma or drug‑induced cases. |
| Meal pattern | “What did you eat before the event? Any missed meals or irregular eating?” | Missed or delayed meals are the common precipitant in patients on sulfonylureas or insulin; a high‑carb meal followed by rapid fall suggests insulin excess. |
| Medication review | “What antidiabetic drugs are you taking? Any recent dose changes? Use of quinine, beta‑blockers, salicylates, or herbal preparations?” | Sulfonylureas, insulin, quinine (malaria treatment) and some antibiotics can provoke hypoglycaemia. Beta‑blockers mask adrenergic symptoms. |
| Co‑morbidities | “Do you have HIV, TB, malaria, sickle‑cell disease, chronic liver disease, renal failure, or adrenal insufficiency?” | HIV/TB therapy (e.g., rifampicin) alters drug metabolism; malaria and sickle‑cell crises increase glucose utilisation; liver/renal disease impairs gluconeogenesis and drug clearance. |
| Alcohol intake | “Do you drink alcohol? How much and when?” | Alcohol inhibits gluconeogenesis and can precipitate delayed hypoglycaemia, especially in malnourished patients. |
| Symptoms | “Do you feel shaky, sweaty, hungry, palpitations, anxiety, headache, visual changes, confusion, seizures or loss of consciousness?” | Autonomic (adrenergic) symptoms reflect catecholamine surge; neuroglycopenic symptoms indicate brain glucose deprivation. |
| Previous episodes | “Have you had similar episodes before? How were they treated?” | Recurrent episodes suggest chronic risk (e.g., insulinoma, medication error). |
| Family history | “Any relatives with diabetes, endocrine tumours, or inherited metabolic disorders?” | Familial hyperinsulinism or MODY may be relevant in younger patients. |
| Pregnancy status | “Are you pregnant?” | Pregnancy increases insulin sensitivity and risk of hypoglycaemia, especially in insulin‑treated diabetics. |
Examination findings and rationale
| Finding | Expected result | Pathophysiological explanation |
|---|---|---|
| Vital signs | Tachycardia, mild hypertension, sweating | Catecholamine release (epinephrine, norepinephrine) stimulates heart rate and peripheral vasoconstriction. |
| Neurological exam | Confusion, dysarthria, focal deficits (rare), seizures if severe | Neuroglycopenia impairs cortical function; severe depletion can provoke seizures. |
| Skin | Diaphoresis, pallor | Sympathetic activation and peripheral vasoconstriction. |
| Mental status | Irritability, anxiety, lethargy, stupor, coma (graded by severity) | Direct effect of low glucose on neuronal metabolism. |
| Cardiac exam | Usually normal; may hear a rapid pulse | Reflex tachycardia from adrenergic surge. |
| Abdominal exam | Usually unremarkable; may note hepatomegaly in chronic liver disease | Liver disease reduces glycogen stores, predisposing to fasting hypoglycaemia. |
| Signs of chronic disease | Lymphadenopathy (TB), splenomegaly (malaria), joint deformities (rheumatic fever) | Underlying infections or inflammatory states can increase glucose utilisation or alter drug metabolism. |
Differential diagnosis
| Condition | Points toward it | Distinguishing feature |
|---|---|---|
| Insulin‑oma | Fasting hypoglycaemia, weight gain, no exogenous insulin use | Inappropriate high insulin & C‑peptide during hypoglycaemia; imaging of pancreas. |
| Sulfonylurea overdose / misuse | Recent sulfonylurea prescription, missed meals | High insulin with suppressed C‑peptide (if exogenous insulin) vs. elevated C‑peptide with sulfonylureas. |
| Adrenal insufficiency | Chronic fatigue, hyperpigmentation, recent stress, TB history | Low cortisol, high ACTH; hyponatraemia, hyperkalaemia. |
| Sepsis / severe malaria | Fever, chills, recent travel, malaria smear positive | Elevated lactate, inflammatory markers; hypoglycaemia due to increased utilisation. |
| Renal failure | Known CKD, uremic symptoms, recent contrast | Impaired insulin clearance; insulin levels may be normal‑high. |
| Hepatic failure | Jaundice, ascites, known hepatitis | Low glycogen stores, low gluconeogenic enzymes; low insulin clearance. |
| Alcohol‑induced hypoglycaemia | Recent binge, poor nutrition | Low glucose after 6‑12 h of drinking; normal insulin & C‑peptide. |
Investigations
| Test | What it answers | Interpretation |
|---|---|---|
| Capillary glucose (point‑of‑care) | Immediate glucose level | < 2.8 mmol/L confirms hypoglycaemia; repeat if symptomatic. |
| Venous plasma glucose + insulin + C‑peptide (during episode) | Distinguish endogenous vs. exogenous insulin excess | High insulin + high C‑peptide → endogenous (insulinoma, sulfonylurea); high insulin + low C‑peptide → exogenous insulin. |
| Sulfonylurea screen | Detect sulfonylurea presence | Positive → drug‑induced hypoglycaemia. |
| CBC, malaria smear, blood cultures | Identify infection as precipitant | Parasitaemia, leukocytosis, positive cultures support sepsis/malaria. |
| Serum cortisol (8 am) ± ACTH stimulation | Assess adrenal function | Low cortisol → adrenal insufficiency. |
| Liver function tests, INR | Evaluate hepatic synthetic capacity | Elevated transaminases, low albumin suggest liver disease. |
| Renal function (creatinine, eGFR) | Check renal clearance of insulin | Reduced eGFR supports impaired insulin clearance. |
| Abdominal imaging (CT/MRI) if insulinoma suspected | Locate pancreatic neuroendocrine tumour | Focal enhancing lesion in pancreas. |
Diagnosis and severity
- Confirm hypoglycaemia – Whipple’s triad: (a) symptoms consistent with low glucose, (b) measured plasma glucose ≤ 2.8 mmol/L, (c) relief of symptoms after glucose administration.
- Classify severity (based on clinical state and glucose level)
| Severity | Glucose (mmol/L) | Clinical picture |
|---|---|---|
| Mild | 2.2 – 2.8 | Autonomic symptoms only; patient alert, able to cooperate. |
| Moderate | 1.7 – 2.1 | Neuroglycopenic signs (confusion, dysarthria) but still responsive. |
| Severe | < 1.7 | Seizures, loss of consciousness, coma; requires airway protection. |
- Assign aetiology – Use the investigation panel to determine whether the cause is endogenous hyperinsulinism, drug‑induced, organ failure, infection, endocrine insufficiency, or alcohol‑related.
- Document – Record glucose values, timing, precipitating factors, and response to treatment. This forms the basis for definitive management and future prevention.
Management
Immediate stabilisation
| Step | Action | Rationale |
|---|---|---|
| 1 | Check airway, breathing, circulation; give supplemental O₂ if SpO₂ < 94 % | Prevent hypoxic injury while glucose is being restored |
| 2 | Obtain a rapid bedside capillary glucose (glucometer) | Confirms true hypoglycaemia (≤ 2.8 mmol/L) before treatment |
| 3 | If patient is unconscious, seizing or unable to swallow → give IV dextrose 50 % (or glucagon IM/SC if IV unavailable) | Rapidly raises plasma glucose and stops neuroglycopenic symptoms |
| 4 | If conscious and able to swallow → give oral glucose (e.g., 15 g rapid‑acting carbohydrate such as glucose tablets, fruit juice, or sugary soft drink) | Safe, avoids IV line in stable patients |
| 5 | Re‑measure glucose after 15 min; repeat step 3/4 if still ≤ 2.8 mmol/L | Ensures adequate correction |
Definitive treatment
- Identify and treat the underlying cause – stop offending insulin or sulfonylurea, treat infection (e.g., malaria, TB, HIV‑related opportunistic infection), correct adrenal insufficiency, manage hepatic failure, etc.
- Adjust anti‑diabetic regimen – for insulin‑treated patients, reduce dose or change timing; for sulfonylurea users, consider switching to a drug with lower hypoglycaemia risk (e.g., DPP‑4 inhibitor).
- Nutritional support – regular meals with complex carbohydrates; consider a bedtime snack for patients on long‑acting insulin.
- Education – teach patients and caregivers the “15‑15 rule” (15 g carbohydrate, re‑check in 15 min) and how to use glucagon kits.
Monitoring
- Continuous glucose monitoring or bedside capillary checks every 30 min until stable, then before meals and at bedtime.
- Observe for recurrent episodes for at least 24 h after the precipitating factor is corrected.
- In ICU/ward, monitor electrolytes (especially potassium) after large dextrose bolus.
Follow‑up
- Review anti‑diabetic plan within 48 h.
- Screen for adrenal, hepatic, renal dysfunction if cause remains unclear.
- Arrange diabetes education session before discharge.
Contra‑indications & safety
- Do not give dextrose to a patient with known hyperglycaemia or diabetic ketoacidosis without confirming low glucose.
- Avoid rapid‑acting insulin bolus before confirming glucose level.
- Glucagon is contraindicated in patients with pheochromocytoma or known hypersensitivity.
- Ensure IV lines are patent; avoid extravasation of hypertonic dextrose.
Complications and prognosis
- Acute neuronal injury – prolonged glucose < 2.2 mmol/L can cause seizures, coma, permanent cognitive deficits.
- Cardiac arrhythmias – hypokalaemia after dextrose infusion may precipitate ventricular ectopy.
- Rebound hyperglycaemia (“Somogyi effect”) if excessive dextrose is given.
- Infection‑related mortality – in HIV/TB patients, hypoglycaemia often signals severe sepsis; prognosis depends on control of the underlying infection.
- Long‑term – recurrent episodes increase risk of vascular events; proper education markedly improves outcomes.
High‑yield exam points
- Look‑alike conditions: Sepsis‑induced lactic acidosis, adrenal crisis, and insulinoma all present with neuroglycopenia; glucose measurement distinguishes them.
- Commonest wrong first step: Giving oral glucose to an unconscious patient – always secure airway and give IV dextrose or IM glucagon first.
- Examiner bedside question: “What will you do if the bedside glucometer reads 2.5 mmol/L but the patient is already receiving a dextrose infusion?” – Answer: stop the infusion, re‑check with a laboratory sample, and treat as true hypoglycaemia until proven otherwise.
- Key safety point: Always re‑measure glucose 15 min after treatment; do not assume resolution.
- Risk‑factor focus for Kenya: HIV/TB co‑infection, malaria, malnutrition, and use of sulfonylureas in patients with renal impairment.
Clinical case
Case: A 58‑year‑old man with type 2 diabetes on glibenclamide presents to the district hospital after a fall. He is drowsy, BP 100/60 mmHg, pulse 110 bpm, capillary glucose 2.4 mmol/L. He reports a 3‑day history of fever, night sweats and a recent positive malaria rapid test.
Questions
- What is the immediate management?
Give IV 50 % dextrose immediately, re‑check glucose after 15 min, and start antimalarial therapy once stable.
- Which underlying factor is most likely precipitating the hypoglycaemia?
Malaria‑induced hepatic dysfunction reducing gluconeogenesis, combined with sulfonylurea use.
- What education should be provided before discharge?
Switch glibenclamide to a drug with lower hypoglycaemia risk, advise the “15‑15 rule”, ensure a bedtime carbohydrate snack, and emphasize prompt treatment of febrile illnesses.
Practice questions
Question 1
A 32‑year‑old woman with gestational diabetes on diet control is found unconscious on the ward. Capillary glucose is 2.0 mmol/L. What is the next best step?
A. Give oral glucose solution
B. Administer IV 50 % dextrose
C. Start an insulin infusion
D. Give subcutaneous regular insulin
Answer: B. Administer IV 50 % dextrose – Unconscious patients need rapid IV glucose; oral route is unsafe.
Question 2
A 45‑year‑old man on metformin presents with confusion. Glucose is 3.5 mmol/L. Which feature would point toward adrenal insufficiency rather than simple drug‑induced hypoglycaemia?
A. Hyperpigmentation of skin
B. Recent sulfonylurea use
C. Low serum sodium and high potassium
D. Elevated HbA1c
Answer: C. Low serum sodium and high potassium – Electrolyte pattern suggests adrenal crisis.
Question 3
A child with sickle cell disease is receiving quinine for malaria and develops a glucose of 2.6 mmol/L. Which medication should be avoided as a rescue therapy?
A. Oral glucose tablets
B. IV 50 % dextrose
C. IM glucagon
D. Subcutaneous regular insulin
Answer: D. Subcutaneous regular insulin – Insulin would worsen hypoglycaemia; glucagon is preferred if IV access is unavailable.
Question 4
A patient on long‑acting insulin presents with nocturnal hypoglycaemia (glucose 2.3 mmol/L). Which adjustment is most appropriate?
A. Increase the evening insulin dose
B. Add a bedtime snack containing complex carbohydrate
C. Switch to a rapid‑acting insulin only
D. Discontinue insulin altogether
Answer: B. Add a bedtime snack containing complex carbohydrate – Prevents overnight lows without abandoning insulin therapy.
Question 5
During a routine ward round, you find a patient with HIV on efavirenz who has a glucose of 2.9 mmol/L but is asymptomatic. What is the correct approach?
A. Ignore it – asymptomatic hypoglycaemia is benign
B. Give oral glucose and re‑check in 30 min
C. Start IV dextrose immediately
D. Order a fasting lipid profile
Answer: B. Give oral glucose and re‑check in 30 min – Treat mild, asymptomatic hypoglycaemia with oral carbohydrate and monitor; no need for IV dextrose.
Drafted with AI assistance from standard references and reviewed for structure. Check details against your lecture notes and the Kenya MoH guideline.