Dxtective archive
Every past daily case, with its clues, diagnosis and pearl. Newest first.
20 past puzzles, up to Thursday 5 November 2026. Today’s and future puzzles are never shown here.
November 2026
#20 · Thursday 5 November 2026 Medium
Walking on tiptoes
The clues:
- 7-year-old boy who woke up refusing to walk. When he tries, he tiptoes.
- Three days of fever, cough and a runny nose. Half his class is off sick.
- Both calves are tender to squeeze. Strength, reflexes and hips are normal.
- CK 4,200 U/L (normal <200)
- Urine is a normal colour and kidney function is normal
- Nose swab: influenza B detected
Diagnosis: Benign acute childhood myositis
Pearl: Benign acute childhood myositis follows influenza (usually B, sometimes A), mostly in school-age boys, and settles within about a week. Check urine colour and kidney function, as it rarely tips into rhabdomyolysis. The northern hemisphere flu season started early in 2026, with the UK reporting rising cases from October.
Play this puzzle#19 · Wednesday 4 November 2026 Medium
Wetland weekend
The clues:
- 45-year-old woman with painful, stiff hands, wrists and ankles.
- Exhausted. Struggling to open jars for 3 weeks.
- A faint red rash on her trunk came and went in the first week.
- Low-grade fever at the start. No history of joint problems.
- Went camping near coastal wetlands in late summer and was bitten a lot.
- Alphavirus IgM positive, IgG rising on repeat serology
Diagnosis: Ross River virus
Pearl: Australia's commonest mosquito-borne infection. Symptoms can last months. Confirm with paired serology, as a single IgM is often a false positive. Treatment is supportive; it's notifiable in NSW.
Play this puzzle#18 · Tuesday 3 November 2026 Easy
Heavy lids by dinner
The clues:
- 34-year-old woman with double vision when reading at night.
- Her left eyelid droops by evening. Fine in the morning.
- Jaw gets tired chewing steak.
- Pupils normal. No pain. No headache.
- An ice pack on the eyelid for 2 minutes clearly lifts the droop.
- Acetylcholine receptor antibodies positive
Diagnosis: Myasthenia gravis
Pearl: Fatigability is the key feature, so examine with sustained upgaze. About half of purely ocular cases are antibody-negative. Order a CT chest to look for thymoma.
Play this puzzle#17 · Monday 2 November 2026 Easy
Moon face, thin skin
The clues:
- 41-year-old woman, gained 12 kg mostly around her middle.
- Struggles to get up from a low chair.
- Bruises with minor knocks. Skin feels thin.
- Wide purple stretch marks on her abdomen.
- New hypertension and fasting glucose 7.4 mmol/L
- 1 mg overnight dexamethasone test: 9 am cortisol 310 nmol/L
Diagnosis: Cushing's syndrome
Pearl: Exogenous steroids are the commonest cause, so ask about creams, inhalers, joint injections and supplements. Proximal weakness, easy bruising and wide purple striae are the most discriminating signs.
Play this puzzle#16 · Sunday 1 November 2026 Genius
Burning since childhood
The clues:
- 32-year-old man with burning pain in his hands and feet since he was a boy.
- It's worse in heat, with fever, or during exercise. He barely sweats.
- Clusters of tiny dark red spots around his navel and swimwear area.
- Urine dipstick: protein 2+
- His uncle had kidney failure and a stroke in his 40s.
- Eye exam: whorl-like patterns in both corneas
Diagnosis: Fabry disease
Pearl: An X-linked lysosomal storage disease. Women can be affected too, often more mildly. Childhood burning pain plus reduced sweating is a classic early clue. Enzyme replacement and oral therapies exist, so diagnosis matters.
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October 2026
#15 · Saturday 31 October 2026 Hard
Cold feet
The clues:
- 58-year-old woman with burning pain and coldness in both feet for 2 days.
- Her toes go white, then a dusky blue. Walking a short way makes her calves ache.
- She started clarithromycin for a chest infection 4 days ago.
- Foot pulses are barely felt. Heart rhythm is regular.
- For years she has taken an old migraine tablet a few times a month.
- Angiogram: smooth, tapered narrowing of arteries in both legs. No clots.
Diagnosis: Ergotism (ergotamine toxicity)
Pearl: Clarithromycin blocks CYP3A4, so ergotamine builds up and clamps arteries shut. In the Middle Ages, ergot-infected rye caused ‘St Anthony's fire’. A 1976 paper even blamed the Salem witch trials on it, though historians remain unconvinced. Happy Halloween.
Play this puzzle#14 · Friday 30 October 2026 Hard
Red lumps, big glands
The clues:
- 35-year-old woman with tender red lumps on both shins.
- Swollen, painful ankles. Low-grade fever.
- A dry cough for 4 weeks.
- Not pregnant, no recent sore throat, no new medications.
- Chest X-ray: bilateral hilar lymphadenopathy
- Serum ACE raised · calcium upper normal
Diagnosis: Sarcoidosis (Löfgren syndrome)
Pearl: Erythema nodosum plus bilateral hilar lymphadenopathy plus ankle arthritis is Löfgren syndrome, the acute form of sarcoidosis. It usually settles on its own within 1–2 years and often doesn't need biopsy.
Play this puzzle#13 · Thursday 29 October 2026 Medium
Pain in the neck
The clues:
- 42-year-old man with sudden pain on the left side of his neck and a left-sided headache.
- It began 2 days ago after a vigorous neck stretch at the gym.
- His left upper eyelid droops slightly and his left pupil is small.
- This morning his right hand went clumsy and weak for 20 minutes, then recovered.
- BP 128/80 · ECG: sinus rhythm · Glucose normal
- CT angiogram: long, tapering narrowing of the left internal carotid artery.
Diagnosis: Carotid artery dissection
Pearl: A leading cause of stroke under 50. Neck pain plus a partial Horner's syndrome plus a TIA or stroke is the classic trio. The Horner's is usually partial because sweating fibres to the face travel with the external carotid. Happy World Stroke Day.
Play this puzzle#12 · Wednesday 28 October 2026 Medium
Bowled over
The clues:
- 17-year-old with low back pain for 6 weeks.
- She's a right-arm fast bowler who has just been picked for her state's under-19 women's squad.
- Worse arching backwards and after a long spell. Better with rest. No leg pain or tingling.
- Standing on her left leg and leaning back reproduces pain just left of the spine.
- Plain X-rays of the lumbar spine are normal.
- MRI: bone oedema in the left L4 pars interarticularis.
Diagnosis: Spondylolysis (pars stress fracture)
Pearl: Fast bowlers usually stress the pars on the side opposite the bowling arm, at L4 or L5, often around 17 or 18 when workloads jump. Plain films miss early injuries. With a Test series on this week, the quicks are earning their ice baths.
Play this puzzle#11 · Tuesday 27 October 2026 Easy
Lifting the baby
The clues:
- 31-year-old woman with pain on the thumb side of her wrist for 4 weeks.
- Her baby is 3 months old. Scooping him out of the cot makes it much worse.
- Wringing out a cloth sends pain up the forearm.
- Tender, slightly swollen spot just above the base of the thumb. No numbness or tingling.
- Tucking the thumb into a fist and tilting the wrist towards the little finger reproduces the pain.
- Ultrasound: thickened sheath around the tendons of the first extensor compartment.
Diagnosis: De Quervain's tenosynovitis
Pearl: Abductor pollicis longus and extensor pollicis brevis rub in their tunnel. Very common after a new baby. OTs and hand therapists often make a thumb splint and teach easier ways to lift. Happy World OT Day.
Play this puzzle#10 · Monday 26 October 2026 Easy
Brushing hurts
The clues:
- 74-year-old woman with a new headache over 3 weeks. She never gets headaches.
- Her scalp is tender when she brushes her hair.
- Her jaw aches after chewing for a minute, then eases with rest.
- Aching shoulders and hips in the morning. Lost 3 kg.
- ESR 92 mm/h · CRP 68 mg/L
- Yesterday her vision went blurry in one eye for 10 minutes.
Diagnosis: Giant cell arteritis
Pearl: Transient visual loss is a warning before permanent blindness. Start high-dose prednisolone the same day and arrange urgent ultrasound or biopsy. Steroids don't spoil the biopsy for 1–2 weeks.
Play this puzzle#9 · Sunday 25 October 2026 Genius
Swelling with no itch
The clues:
- 23-year-old woman with recurrent swelling of her hands and lips.
- Each episode lasts 2–4 days. No hives. No itch.
- Antihistamines, steroids and even adrenaline don't help.
- Twice she's had severe abdominal pain and vomiting. Scans showed swollen bowel wall.
- Swelling followed a dental procedure. It worsened on the combined pill.
- C4 low · C1-inhibitor level low
Diagnosis: Hereditary angioedema
Pearl: Swelling without hives that doesn't respond to anaphylaxis treatment points away from allergy. It's bradykinin, not histamine. Low C4 between attacks is a good screen. Throat swelling is life-threatening and needs C1-inhibitor or icatibant.
Play this puzzle#8 · Saturday 24 October 2026 Hard
Bendy and dizzy
The clues:
- 22-year-old woman with widespread joint pain since her teens.
- Her shoulders have partly dislocated several times with minor movements.
- Soft, velvety, slightly stretchy skin. Wide, thin scars.
- Dizzy and racing heart on standing for long periods.
- Her mother was always 'double-jointed'.
- Beighton score 7/9
Diagnosis: Hypermobile Ehlers-Danlos syndrome (hEDS)
Pearl: hEDS is a clinical diagnosis using the 2017 criteria; there's no genetic test for it. It often travels with POTS. Thin, translucent skin, arterial or organ rupture point to vascular EDS, which needs urgent genetics referral.
Play this puzzle#7 · Friday 23 October 2026 Hard
Copper eyes
The clues:
- 19-year-old man whose handwriting has deteriorated over a year.
- A tremor that gets worse when he holds his arms out.
- Family say he's become irritable and his marks have dropped.
- ALT mildly raised. Not drinking, no medications.
- Golden-brown ring at the edge of each cornea.
- Caeruloplasmin low
Diagnosis: Wilson disease
Pearl: Consider it in anyone under 40 with unexplained liver disease plus neurological or psychiatric change. Kayser-Fleischer rings may need a slit lamp. It's treatable, and siblings need screening.
Play this puzzle#6 · Thursday 22 October 2026 Medium
Standing ovation
The clues:
- 24-year-old woman. Dizzy and foggy since a viral illness 6 months ago.
- Heart pounds when she stands in the shower queue or at the checkout.
- Feels better lying down. Worse in heat and after big meals.
- ECG normal. FBC, TSH, ferritin and cortisol all normal.
- Lying: HR 68, BP 112/70 · Standing 10 min: HR 112, BP 110/72
- Symptoms persist over 3 months. No orthostatic hypotension.
Diagnosis: POTS (postural orthostatic tachycardia syndrome)
Pearl: Sustained HR rise of 30+ bpm (40+ under 20) within 10 minutes of standing, without a BP drop, plus 3+ months of symptoms. A GP-room active stand test does the job before any tilt table.
Play this puzzle#5 · Wednesday 21 October 2026 Medium
Rusty joints
The clues:
- 52-year-old man, tired for a year. "Just getting old, doc."
- Painful 2nd and 3rd MCP joints, both hands. Squeezing a handshake hurts.
- Partner says he looks tanned all year. He works in an office.
- New diagnosis of type 2 diabetes last month. BMI 23.
- ALT 88 U/L · Ferritin 1,450 µg/L
- Transferrin saturation 78%
Diagnosis: Hereditary haemochromatosis
Pearl: Ferritin alone is non-specific. A transferrin saturation over 45% is the clue to order HFE genotyping. Hook-like osteophytes on the 2nd/3rd MCPs are the classic X-ray sign.
Play this puzzle#4 · Tuesday 20 October 2026 Easy
Bones, stones, groans
The clues:
- 58-year-old woman, recently passed a kidney stone.
- Constipated, thirsty, up twice a night to pass urine.
- Says her mood has been flat and she feels 'foggy'.
- Aching bones. Not on any supplements.
- Corrected calcium 2.85 mmol/L (ref 2.10–2.60)
- PTH 9.8 pmol/L (ref 1.6–6.9) · Vitamin D normal
Diagnosis: Primary hyperparathyroidism
Pearl: High calcium with a PTH that isn't suppressed means primary hyperparathyroidism until proven otherwise. Check a 24-hour urine calcium to exclude familial hypocalciuric hypercalcaemia before referral.
Play this puzzle#3 · Monday 19 October 2026 Easy
Iron that won't stick
The clues:
- 29-year-old woman, tired for two years.
- Iron deficiency anaemia that hasn't improved despite 6 months of oral iron.
- Intermittent bloating and recurrent mouth ulcers.
- DEXA after a wrist fracture shows osteopenia. She's premenopausal.
- Her sister has type 1 diabetes.
- tTG-IgA 120 U/mL (ref <15) · Total IgA normal
Diagnosis: Coeliac disease
Pearl: Test while she is still eating gluten, and check total IgA or the result can be falsely negative. Iron deficiency that fails oral replacement should prompt coeliac serology.
Play this puzzle#2 · Sunday 18 October 2026 Genius
Don't scratch that
The clues:
- 41-year-old man with episodes of flushing and a pounding heart.
- Diarrhoea and cramps after hot showers or alcohol.
- Small reddish-brown spots on his trunk for years.
- When a spot is rubbed, it swells into a hive within minutes.
- Anaphylaxis to a wasp sting last summer. DEXA: osteoporosis at 41.
- Baseline serum tryptase 48 µg/L
Diagnosis: Systemic mastocytosis
Pearl: Rubbing a spot until it hives is Darier's sign. A baseline tryptase above 20 µg/L is a diagnostic criterion. Anyone with insect-sting anaphylaxis and a high baseline tryptase should be checked for mastocytosis.
Play this puzzle#1 · Saturday 17 October 2026 Hard
Toasty shins
The clues:
- 71-year-old woman with a painless rash on the fronts of both shins.
- Net-like, reddish-brown pattern. Not itchy, not raised.
- The backs of her legs are completely spared.
- It appeared over winter and has slowly darkened.
- Lives alone in an old, poorly insulated house.
- Spends every evening with a bar heater about 30 cm from her legs.
Diagnosis: Erythema ab igne
Pearl: Chronic low-level heat causes reticulated pigmentation. Modern versions come from laptops on thighs and heat packs. Remove the heat source; biopsy only if a lesion ulcerates or changes, as SCC can rarely develop.
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