(a) A 20-year-old male has presented to the medicine OPD. He has complaints of episodes of breathlessness associated with…

(a)(i) Most probable diagnosis

Bronchial asthma (allergic, childhood onset): recurrent, seasonal, reversible airway obstruction with wheeze, chest tightness and breathlessness.

(a)(ii) Confirming the diagnosis

Spirometry shows airflow obstruction (reduced FEV₁/FVC) with reversibility, an increase in FEV₁ of more than 12% and 200 mL after salbutamol. Peak expiratory flow variability of more than 10% over one to two weeks of home monitoring. When spirometry is normal, a bronchial provocation test (methacholine or exercise challenge) shows hyper-responsiveness. Supportive: blood eosinophilia, raised IgE, positive skin-prick tests, raised exhaled nitric oxide, and a chest X-ray to exclude other causes.

(a)(iii) Clinical features

Recurrent episodes of breathlessness, wheeze, chest tightness and cough, worse at night or early morning, and triggered by seasonal allergens (pollen, dust mite, mould), cold air, exercise, infections and smoke. Atopy: allergic rhinitis, eczema, and a family history. Between attacks the chest is normal. In an attack: tachypnoea, use of accessory muscles, prolonged expiration with diffuse polyphonic wheeze, and hyperinflation. Life-threatening signs: silent chest, cyanosis, inability to speak, exhaustion, bradycardia and altered sensorium.

(a)(iv) Stepwise management

First educate the patient, avoid triggers, check inhaler technique and adherence, treat rhinitis, and give a written action plan. Treatment is stepped up or down by control (GINA). Step 1: as-needed low-dose inhaled corticosteroid (ICS)-formoterol; where a short-acting β₂ agonist (salbutamol) is used as reliever, it is taken together with ICS. Step 2: daily low-dose ICS with a reliever, or as-needed ICS-formoterol. Step 3: low-dose ICS-long-acting β₂ agonist (LABA), as maintenance and reliever therapy with ICS-formoterol. Step 4: medium-dose ICS-LABA. Step 5: high-dose ICS-LABA with add-on tiotropium or a leukotriene antagonist, and biologics (omalizumab, mepolizumab, dupilumab) for severe allergic or eosinophilic asthma; oral steroids only as a last resort. Allergen immunotherapy may help in selected patients. Acute attack: oxygen, nebulised salbutamol with ipratropium, systemic corticosteroid (prednisolone 40 to 50 mg for 5 to 7 days), intravenous magnesium sulphate if severe, and ventilation if exhausted.

(b)(i) Criteria for identifying severe acute malnutrition (6 to 59 months)

Any one of: Weight-for-height (or length) below −3 standard deviations of the WHO growth standards. Mid-upper arm circumference below 11.5 cm. Bilateral pitting oedema of the feet, of any grade (nutritional oedema).

(b)(ii) Criteria for admission to facility-based care

Complicated SAM, that is SAM with any of the following: Bilateral pitting oedema of grade 3 (or oedema with severe wasting). Failed appetite test (cannot eat the therapeutic food). Any medical complication or danger sign: poor feeding, vomiting, convulsions, lethargy or unconsciousness, severe dehydration, hypoglycaemia, hypothermia, high fever, severe anaemia, pneumonia, sepsis, severe diarrhoea, measles or HIV. Infants below 6 months with SAM. Failure to gain weight or deterioration on community-based management. Poor caregiver support where home care is unsafe.

(b)(iii) Ten steps in the management of SAM

1. Treat or prevent hypoglycaemia: feed at once or give 10% glucose or sugar solution; feed every 2 to 3 hours.
2. Treat or prevent hypothermia: keep the child warm, kangaroo care, cover the head.
3. Treat or prevent dehydration with ReSoMal (5 mL/kg every 30 minutes for 2 hours, then 5 to 10 mL/kg/hour); intravenous fluid only for shock.
4. Correct electrolyte imbalance: potassium and magnesium supplements, low-sodium diet.
5. Treat or prevent infection with broad-spectrum antibiotics (amoxicillin, with gentamicin in complications) and measles vaccine.
6. Correct micronutrient deficiency: vitamin A, folic acid, zinc and copper; iron only after weight gain starts (after about 2 weeks).
7. Start cautious feeding with F-75 (about 100 kcal/kg/day in 8 feeds) in the stabilisation phase.
8. Achieve catch-up growth with F-100 or ready-to-use therapeutic food (150 to 220 kcal/kg/day), aiming at weight gain above 10 g/kg/day.
9. Provide sensory stimulation, play and emotional support.
10. Prepare for discharge and follow-up: counsel the mother on feeding, give RUTF, keep immunisation up to date and arrange follow-up.

(c) Role of X-ray imaging in the diagnosis of acute abdomen

Plain films (erect chest, supine and erect abdomen, or left lateral decubitus if the patient cannot stand) are quick, cheap and available, and give first triage; CT is more sensitive. Perforation: free gas under the diaphragm on the erect chest film (pneumoperitoneum), with the double-wall (Rigler) and falciform ligament signs on the supine film. Intestinal obstruction: dilated bowel loops (small bowel over 3 cm, large bowel over 6 cm, caecum over 9 cm), step-ladder air-fluid levels on the erect film, valvulae conniventes or haustra, and little or no gas in the rectum. Sigmoid volvulus shows the coffee-bean sign. Paralytic ileus: generalised gas-filled loops; sentinel loop and colon cut-off sign in pancreatitis; toxic megacolon. Calcifications and stones: radio-opaque renal and ureteric calculi, a faecolith (appendicolith), gallstones (only 10 to 15%), pancreatic calcification and a calcified aortic aneurysm. Other signs: pneumobilia (gallstone ileus), portal venous gas and pneumatosis (ischaemia, necrotising enterocolitis), obliterated psoas shadow and flank stripe (retroperitoneal collection or ascites), and foreign bodies. Limitations: normal films do not exclude disease; ultrasound and CT are needed for appendicitis, cholecystitis, pancreatitis and vascular causes.