(a) A 20-year-old medical student presents with fever, dry cough, and right-sided chest pain. She also has loss of weight and…

(a) A 20-year-old with fever, dry cough, chest pain, weight loss and right pleural effusion (20 marks)

Working diagnosis. In India, a unilateral pleural effusion with fever, weight loss and anorexia in a young adult is a tubercular pleural effusion until proved otherwise. It is a delayed hypersensitivity response to mycobacterial antigens in the pleura, and it usually clears without treatment, but most untreated patients (up to about two-thirds) develop active TB within 5 years, so treatment is always given. The differential diagnosis includes parapneumonic effusion, malignancy (lymphoma), connective tissue disease (SLE), pulmonary embolism and a viral pleurisy.

Diagnostic investigations.

• History and examination: contact history (she is a medical student, so hospital exposure), HIV risk. Signs: a stony dull percussion note, reduced breath sounds and vocal resonance, and a shifted trachea and mediastinum if the effusion is massive.
• Imaging: the chest X-ray shows blunting of the costophrenic angle and a meniscus sign (at least 200–300 mL of fluid), and may show a parenchymal lesion. Ultrasound confirms the fluid, shows septation or loculation, and marks the site for a tap. CT is used when the diagnosis is unclear.
• Diagnostic thoracentesis (the key test). The fluid is straw-coloured, and is an exudate by Light's criteria (any one of: pleural fluid protein/serum protein above 0.5; pleural fluid LDH/serum LDH above 0.6; pleural fluid LDH above two-thirds of the upper normal limit of serum). Typical findings are a lymphocyte-predominant cell count (above 50% lymphocytes), few mesothelial cells (under 5%), a low or normal glucose, and a pH usually above 7.3.
• Adenosine deaminase (ADA): a level above 40 U/L in a lymphocytic exudate strongly supports TB (high sensitivity and specificity in a high-prevalence setting). Interferon-gamma is an alternative.
• Microbiology: AFB smear (rarely positive, below 10%), CBNAAT on the fluid (low sensitivity, about 30–50%, but specific) and liquid culture (MGIT), which give a definite diagnosis. Sputum, if produced (or induced), is sent for CBNAAT and culture, as the lung may be involved. Cytology excludes malignancy.
• Pleural biopsy: if fluid tests are inconclusive, a closed needle (Abram's or Cope's) biopsy shows caseating granulomas (yield 60–80%), and medical thoracoscopy with directed biopsy gives 90% or more.
• Supporting tests: Mantoux test or interferon-gamma release assay (supportive only), HIV test, complete blood count, ESR, liver and kidney function, and blood sugar (baseline before treatment). ANA is added if SLE is suspected.

Management (as per the National TB Elimination Programme).

• Anti-tubercular treatment: a drug-sensitive regimen of 2 months of isoniazid, rifampicin, pyrazinamide and ethambutol (2HRZE) followed by 4 months of isoniazid, rifampicin and ethambutol (4HRE), all given daily as fixed-dose combinations by weight band. The doses are isoniazid 5 mg/kg, rifampicin 10 mg/kg, pyrazinamide 25 mg/kg and ethambutol 15 mg/kg. Add pyridoxine (10 mg daily) if risk factors for neuropathy exist. Before starting, check baseline liver function and follow up for hepatotoxicity.
• Fluid drainage: therapeutic thoracentesis is done for a large effusion causing breathlessness, removing not more than 1–1.5 L at a time to avoid re-expansion pulmonary oedema. If the fluid is turbid or pus (empyema, pH below 7.2), an intercostal drain is placed. Chest physiotherapy helps to reduce pleural thickening. Corticosteroids are not used routinely.
• Monitoring: clinical response (fever settles in 2–4 weeks), chest X-ray at 2 months and at the end of treatment, monitoring for residual pleural thickening, and sputum follow-up if it was positive. Watch for drug-induced hepatitis.
• Programme measures: notify the case on the Nikshay portal, provide a treatment supporter and the Nikshay Poshan Yojana nutrition support (₹1000 a month), screen household contacts and give them TB preventive treatment where indicated, counsel on adherence to prevent drug resistance, and check the HIV status.

(b) A 2-year-old boy, weight 8 kg, length 72 cm (5 + 5 + 5 + 5 = 20 marks)

(b)(i) Assessment and classification (5 marks)

Malnutrition is assessed with the WHO child growth standards, using weight-for-age, length/height-for-age, weight-for-length/height, mid-upper-arm circumference (MUAC), and a check for bilateral pitting oedema, along with a dietary, immunisation and socio-economic history.

• Weight-for-age: the WHO median for a boy of 24 months is 12.2 kg and the −3 SD value is 8.6 kg. His 8 kg is below −3 SD, so he is severely underweight.
• Length-for-age: 72 cm is far below the −3 SD value for 24 months (about 77 cm), so he is severely stunted, which indicates chronic malnutrition.
• Weight-for-length: at 72 cm the WHO values are median 8.9 kg, −2 SD 7.6 kg and −3 SD 7.0 kg. His 8 kg lies between −1 and −2 SD, so he is not wasted by this index.
• SAM: severe acute malnutrition is defined by weight-for-length below −3 SD, or MUAC below 11.5 cm, or bilateral pitting oedema, and moderate acute malnutrition by weight-for-length between −3 and −2 SD or MUAC of 11.5–12.5 cm. This boy meets the criteria for severe stunting and severe underweight; he is classed as SAM only if the MUAC is below 11.5 cm or oedema is present, which must be examined at once. Other classifications (Gomez, Waterlow and IAP) also grade him as severely malnourished, with chronic malnutrition.

(b)(ii) Clinical features and complications (5 marks)

Clinical features. Severe malnutrition presents as one of three forms.

• Marasmus: severe wasting with loss of subcutaneous fat and muscle, an "old man" face, prominent ribs and baggy skin folds, an alert, irritable and hungry child, without oedema.
• Kwashiorkor: bilateral pitting oedema (the feet first), a moon face, apathy and misery, flaky-paint dermatosis, sparse light "flag sign" hair, and an enlarged fatty liver.
• Marasmic kwashiorkor: wasting with oedema.
• Signs of micronutrient deficiency: pallor, angular stomatitis and glossitis, Bitot's spots (vitamin A), rickets and scurvy.

Complications.

• Hypoglycaemia, hypothermia, dehydration with electrolyte imbalance (low potassium and magnesium, high total body sodium), and shock.
• Infections that show few signs: pneumonia, diarrhoea, sepsis, urinary tract infection and tuberculosis.
• Severe anaemia, heart failure (especially with fluid overload) and refeeding problems, and vitamin A deficiency with corneal ulceration.
• Long-term: impaired growth, immunity and intellectual development, and a high mortality.

(b)(iii) Stepwise management of severe acute malnutrition (5 marks)

The WHO 10-step approach is followed in two phases, initial stabilisation (days 1–7) and rehabilitation.

• Step 1, hypoglycaemia: feed immediately, or give 10% glucose (5 mL/kg) by mouth or nasogastric tube, or IV if unconscious; then feed 2-hourly.
• Step 2, hypothermia: keep warm (skin-to-skin, blankets), and treat if temperature is below 35.5 °C.
• Step 3, dehydration: use low-sodium ReSoMal (5 mL/kg every 30 minutes for 2 hours, then 5–10 mL/kg/hour); IV fluid only for shock, slowly. Avoid standard ORS and overhydration.
• Step 4, electrolytes: give potassium (3–4 mmol/kg/day) and magnesium for 2 weeks, and prepare food without added salt.
• Step 5, infection: give routine antibiotics (oral amoxicillin for 5 days, or ampicillin with gentamicin, or ceftriaxone if complicated), and treat any tuberculosis, malaria or HIV.
• Step 6, micronutrients: vitamin A on day 1, folic acid, zinc (2 mg/kg/day), copper and multivitamins; no iron until the child is gaining weight.
• Step 7, cautious feeding: F-75 (75 kcal and 0.9 g protein per 100 mL), about 130 mL/kg/day (100 kcal/kg/day), which is about 1040 mL a day for 8 kg, in 8–12 small feeds.
• Step 8, catch-up growth: see the rehabilitation phase below.
• Step 9, sensory stimulation and emotional support: play, and the mother's involvement.
• Step 10, prepare for follow-up: immunisation, counselling of the mother on feeding, treatment of the underlying illness, and discharge when weight-for-length is above −2 SD (or as per the local criterion), with home follow-up.

(b)(iv) Dietary management in the rehabilitation phase (5 marks)

The rehabilitation phase begins when the appetite returns, the child has no oedema or complications, and he is alert (usually from the end of the first week).

• Transition: replace F-75 with F-100 (100 kcal and 2.9 g protein per 100 mL) or ready-to-use therapeutic food (RUTF) in the same volume for 2 days, to avoid heart failure.
• Catch-up feeding: increase the intake to F-100 of 150–220 mL/kg/day (150–220 kcal/kg/day and 4–6 g protein/kg/day, which is about 1200–1760 mL a day for 8 kg), in 5–6 feeds. RUTF at about 200 kcal/kg/day can be used, with clean water to drink.
• Family food: introduce energy-dense, locally available foods (khichdi with oil, milk-based preparations, mashed fruits and pulses), continue breastfeeding, and add iron (3 mg/kg/day) once he is gaining weight.
• Monitoring: weigh daily and target a gain of at least 10 g/kg/day; if the gain is below 5 g/kg/day, look for infection, inadequate intake or an underlying disease (tuberculosis, HIV).
• Stimulation and counselling: continue play and emotional support, and counsel the mother on complementary feeding, hygiene and immunisation.

(c) A 1-month-old infant with greasy yellow scaling of the scalp and erythema of the folds (3 + 3 + 4 = 10 marks)

(i) Diagnosis (3 marks). Infantile seborrhoeic dermatitis: cradle cap of the vertex and frontal scalp, with a flexural rash (retroauricular and nasolabial folds). It is common in the first 3 months and is usually not itchy.

(ii) Aetiology (3 marks). The cause is not fully known. The contributing factors are:

• Overactivity of the sebaceous glands in early life, driven by maternal and neonatal androgens.
• The lipophilic yeast Malassezia (formerly Pityrosporum), which lives on the skin and provokes an inflammatory response through its metabolism of the sebum lipids.
• An altered skin barrier and local immune response. It is not an infection or an allergy, and it is not caused by poor hygiene.

(iii) Management (4 marks). The disorder is self-limiting, and usually clears by 6–12 months.

• Reassure the parents, and explain that it is harmless and does not itch.
• Scalp: soften the scales with a bland oil (olive or mineral oil) for a few hours, then wash with a mild baby shampoo and remove the loosened scales gently with a soft brush. For thick or persistent scale, use 2% ketoconazole shampoo two or three times a week.
• Folds and face: keep them clean and dry, and apply a topical antifungal such as 2% ketoconazole or ciclopirox cream; a short course (3–5 days) of a mild steroid such as 1% hydrocortisone is used only for marked inflammation. Avoid potent steroids and occlusion.
• Follow up, and look for other causes if the rash is extensive, resistant or associated with failure to thrive, diarrhoea or recurrent infection (atopic dermatitis, Langerhans cell histiocytosis, immunodeficiency and Leiner's disease).