DOH, DHA & MOH GP (General Practitioner) Exam Questions

Why correct: In a young woman of reproductive age presenting with suspected acute appendicitis, transabdominal ultrasonography (graded compression ultrasound) is the recommended first-line imaging modality. This approach is endorsed by multiple guidelines including the EAES 2015 consensus and the American College of Radiology Appropriateness Criteria (2019 revision). Ultrasonography avoids ionising radiation, which is particularly important in young women, and can simultaneously evaluate gynaecological pathology (ovarian torsion, ruptured ovarian cyst, ectopic pregnancy) that may mimic appendicitis. In experienced hands, USS has a sensitivity of 71–94% and specificity of 81–98% for appendicitis. An Alvarado score of 8 is high (≥7 indicates high probability of appendicitis), but the surgical team has specifically requested imaging confirmation, and ultrasound serves as the appropriate initial step. If ultrasound is inconclusive, CT can then be considered as a second-line investigation.

Why A wrong: Abdominal radiograph has extremely limited sensitivity and specificity for appendicitis. A faecolith may occasionally be visible, but plain radiographs cannot reliably confirm or exclude appendicitis and are not recommended for this purpose by any current guideline.

Why B wrong: Contrast-enhanced CT abdomen and pelvis has the highest sensitivity (94–98%) and specificity (95–98%) for diagnosing appendicitis. However, it exposes the patient to significant ionising radiation (approximately 8–10 mSv) and is therefore not the recommended first-line modality in young women of reproductive age. CT is reserved as a second-line investigation when USS is inconclusive, per the ACR Appropriateness Criteria (2019) and WSES Jerusalem Guidelines (2020).

Why C wrong: Diagnostic laparoscopy is an invasive surgical procedure that can be both diagnostic and therapeutic. However, proceeding directly to laparoscopy bypasses non-invasive imaging and carries risks of general anaesthesia and surgical complications. It is not appropriate as a first-line diagnostic imaging step when non-invasive options are available.

Why D wrong: MRI abdomen and pelvis is an excellent radiation-free modality with high sensitivity and specificity for appendicitis. It is the preferred imaging in pregnant patients when USS is inconclusive. However, in a non-pregnant young woman, MRI is not the standard first-line investigation due to higher cost, limited availability, longer scan times, and the need for patient cooperation. Ultrasound remains the initial choice.

Key learning point: In young women of reproductive age with clinically suspected appendicitis, transabdominal ultrasound is the first-line imaging modality to avoid ionising radiation and to simultaneously exclude gynaecological differential diagnoses. CT is reserved for cases where ultrasound is inconclusive.

The most likely diagnosis is Colles' fracture — the most common wrist fracture in postmenopausal women with osteoporosis following a FOOSH mechanism. Its hallmark radiographic features are dorsal displacement and dorsal angulation of the distal radial fragment, producing the classic 'dinner fork' deformity clinically (Option A). Option B describes a Smith's fracture (reverse Colles'), caused by a fall on a flexed wrist, producing volar angulation. Option C describes a Barton's fracture, an intra-articular shear fracture of the dorsal or volar radial rim, which is inherently unstable and often requires surgical fixation. Option D describes a scaphoid fracture, which typically presents with anatomical snuffbox tenderness and may be radiographically occult initially — not consistent with the described deformity. Pearl: In a postmenopausal woman sustaining a fragility wrist fracture, initiation of osteoporosis treatment (bisphosphonate ± calcium/vitamin D) should be considered, as this event signals high future fracture risk per NICE NG187 (2023).

The correct answer is C. TSH does NOT convert T4 to T3. T4-to-T3 conversion occurs predominantly in peripheral tissues — liver, kidney, and skeletal muscle — via type 1 and type 2 iodothyronine deiodinase enzymes (encoded by DIO1 and DIO2). Within the thyroid gland itself, only a small fraction (~20%) of T3 is secreted directly; the remaining ~80% of circulating T3 derives from peripheral deiodination of T4. This distinction is clinically relevant: patients on levothyroxine (T4) rely on peripheral conversion for most of their T3, explaining why some symptomatic patients may have impaired conversion despite normal TSH.

Option A is true — TRH from the paraventricular nucleus of the hypothalamus acts on thyrotrophs in the anterior pituitary. Option B is true — TSH upregulates the sodium-iodide symporter (NIS, encoded by SLC5A5). Option D is true — TSH drives thyroglobulin synthesis, iodination, and hormone release. Option E is true and reinforces the teaching point of C.

Reference: Williams Textbook of Endocrinology (14th ed.); NICE NG145 (2023); ATA/AACE Clinical Practice Guidelines.

This lesion fulfils all five ABCDE criteria for melanoma: Asymmetry, Border irregularity, Colour variation (≥3 colours), Diameter >6 mm (15 mm), and Evolution over 6 months. Per NICE NG12 (updated 2023), any suspicious pigmented lesion meeting these features warrants an urgent 2-week-wait referral to a dermatologist for excision biopsy — this is the correct next step, not watchful waiting or GP-level dermoscopy. NICE NG14 (2022) further details assessment and management of suspected melanoma. Reassurance (A, E) is dangerous and incorrect given the high-risk features. Routine 18-week referral (C) introduces unacceptable delay. Topical retinoids (D) have no role in pigmented lesion assessment. Key pearl: in a GP setting, if ≥3 ABCDE criteria are present, treat as melanoma until proven otherwise and refer urgently.

Gestational hypertension (GH) is defined as a sustained BP ≥140/90 mmHg arising after 20 weeks' gestation in a previously normotensive woman, in the absence of proteinuria or other features of pre-eclampsia (NICE NG133, 2023). This patient meets all criteria: new-onset hypertension at 24 weeks, normal booking BP, no proteinuria, and no systemic symptoms. Pre-eclampsia requires proteinuria (≥1+ on dipstick, confirmed by PCR ≥30 mg/mmol) or end-organ involvement (e.g. thrombocytopaenia, renal/hepatic impairment, neurological features) — absent here. Chronic hypertension is diagnosed when BP ≥140/90 predates 20 weeks or antedates pregnancy. GH requires close monitoring: up to 50% progress to pre-eclampsia, so two-weekly BP checks and urinalysis are mandated until delivery. Pearl: reclassification to pre-eclampsia may occur at any point, so the absence of proteinuria at diagnosis does not exclude future progression.