Crystal arthropathies UK Medical PG Practice Questions and MCQs
Practice UK Medical PG questions for Crystal arthropathies. These multiple choice questions (MCQs) cover important concepts and help you prepare for your exams.
Crystal arthropathies UK Medical PG Question 1: A 42-year-old woman presents with fatigue, muscle aches, and widespread pain. She has multiple tender points but normal inflammatory markers. Sleep is poor. What is the most appropriate initial treatment?
- A. NSAIDs
- B. Prednisolone
- C. Pregabalin (Correct Answer)
- D. Methotrexate
- E. Physiotherapy alone
Crystal arthropathies Explanation: ***Pregabalin***
- **Pregabalin** is a **gabapentinoid** drug that modulates voltage-gated calcium channels, decreasing the release of excitatory neurotransmitters involved in central pain sensitization characteristic of **fibromyalgia**.
- It is one of the FDA-approved medications (along with duloxetine and milnacipran) specifically recommended for managing the **widespread pain** and associated symptoms like **poor sleep** in fibromyalgia.
*NSAIDs*
- Non-steroidal anti-inflammatory drugs (NSAIDs) target inflammatory pain, which is generally absent in **fibromyalgia** as evidenced by **normal inflammatory markers**.
- NSAIDs are usually **ineffective** in treating the centralized pain and hyperalgesia seen in this condition, making them a poor choice for monotherapy.
*Prednisolone*
- **Prednisolone** is a powerful corticosteroid used for conditions driven by **inflammation** (e.g., active arthritis or vasculitis).
- The patient has normal inflammatory markers and a clinical presentation consistent with a non-inflammatory central pain syndrome, making steroids **inappropriate** and potentially harmful.
*Methotrexate*
- **Methotrexate** is a **Disease-Modifying Anti-Rheumatic Drug (DMARD)** indicated for managing autoimmune inflammatory diseases like **Rheumatoid Arthritis** or **Psoriatic Arthritis**.
- Since the patient does not show evidence of an inflammatory or autoimmune joint disease, this immunosuppressant drug treatment is **not warranted**.
*Physiotherapy alone*
- While non-pharmacological therapies like **aerobic exercise** and **Cognitive Behavioral Therapy (CBT)** are essential long-term components, they are often insufficient alone to manage severe initial symptoms, particularly **poor sleep** and disabling pain.
- Initial treatment typically requires a combination of pharmacological agents (like **Pregabalin**) combined with supportive non-pharmacological management for optimal symptom control.
Crystal arthropathies UK Medical PG Question 2: A 52-year-old man presents with progressive dysphagia and weight loss. He has tight skin on his hands and Raynaud's phenomenon. What is the most likely esophageal abnormality?
- A. Esophageal carcinoma
- B. Achalasia
- C. Esophageal dysmotility (Correct Answer)
- D. Peptic stricture
- E. Eosinophilic esophagitis
Crystal arthropathies Explanation: ***Esophageal dysmotility***- The combination of **tight skin (scleroderma)** and **Raynaud's phenomenon** is characteristic of **Systemic Sclerosis**, which causes atrophy and fibrosis of smooth muscle in the distal two-thirds of the esophagus.- This loss of smooth muscle function leads to decreased peristalsis (dysmotility) and, crucially, incompetence of the **lower esophageal sphincter (LES)**, causing severe GERD and the resulting dysphagia.*Esophageal carcinoma*- While progressive **dysphagia** and **weight loss** are concerns for malignancy, the patient's systemic features (**tight skin**, **Raynaud's**) strongly suggest a connective tissue disorder as the etiology.- Carcinoma often occurs in the context of significant risk factors (e.g., smoking, alcohol, HPV) and typically does not present with the classic dermatologic or peripheral vascular signs of Scleroderma.*Achalasia*- Achalasia involves impaired relaxation of the **LES** and aperistalsis, but it is a primary esophageal motility disorder and lacks the systemic features (Raynaud's, sclerodactyly) seen in this patient.- Dysphagia in achalasia tends to be prominent for both **liquids and solids** from the start, often without significant GERD symptoms.*Peptic stricture*- A **peptic stricture** is a *consequence* of chronic acid exposure resulting from the incompetent LES caused by Scleroderma-related esophageal dysmotility.- While a stricture may eventually explain the severe dysphagia, the primary diagnostic link between the systemic symptoms and the esophageal pathology is the **underlying smooth muscle failure** (dysmotility).*Eosinophilic esophagitis*- This condition is typically associated with **atopic disorders** (allergies, asthma) and presents histologically with excessive **eosinophil infiltration**.- It typically causes dysphagia, often for solids, and sometimes **food impaction**, but it is not linked to generalized fibrosis or vascular changes like those causing tight skin and Raynaud's phenomenon.
Crystal arthropathies UK Medical PG Question 3: A 48-year-old man presents with progressive muscle weakness affecting proximal muscles. CK is elevated at 3200 U/L. Muscle biopsy shows inflammatory infiltrates. What is the cancer screening recommendation?
- A. No screening needed (Correct Answer)
- B. Chest X-ray only
- C. CT chest/abdomen/pelvis
- D. Colonoscopy only
- E. PSA testing only
Crystal arthropathies Explanation: ***No screening needed***- The clinical presentation of **progressive proximal muscle weakness**, elevated **CK**, and **inflammatory infiltrates** on muscle biopsy is consistent with **polymyositis**.- Unlike **dermatomyositis**, which has a strong association with occult malignancies, **polymyositis** is generally not associated with an increased risk of cancer, therefore **routine cancer screening** is not indicated. *Chest X-ray only*- A **chest X-ray** is a limited screening tool and would be insufficient to detect a wide range of potential malignancies associated with paraneoplastic syndromes.- It would miss cancers in other vital organs, making it an inadequate approach if malignancy were suspected. *CT chest/abdomen/pelvis*- This extensive imaging is typically recommended for patients with **dermatomyositis** due to its strong association with various occult malignancies.- In the absence of dermatomyositis-specific features (e.g., characteristic skin rashes) or other malignancy risk factors, such broad screening is not indicated for **polymyositis**. *Colonoscopy only*- While gastrointestinal malignancies can be associated with paraneoplastic syndromes, performing **colonoscopy** alone is insufficient for comprehensive cancer screening.- This approach would overlook other common cancer sites linked to inflammatory myopathies, such as lung, breast, or ovarian cancers. *PSA testing only*- **PSA testing** is specific for prostate cancer screening and would be part of a more comprehensive workup, not the sole screening measure for malignancy.- Focusing solely on prostate cancer would miss other potential malignancies that might be associated with paraneoplastic syndromes in other forms of inflammatory myopathies.
Crystal arthropathies UK Medical PG Question 4: A 35-year-old woman presents with recurrent miscarriages and thrombosis. She has positive lupus anticoagulant and anticardiolipin antibodies. What is the mechanism of thrombosis?
- A. Platelet activation
- B. Endothelial dysfunction (Correct Answer)
- C. Protein C deficiency
- D. Factor V Leiden mutation
- E. Hyperhomocysteinemia
Crystal arthropathies Explanation: ***Endothelial dysfunction***- This is the primary mechanism in **Antiphospholipid Syndrome (APS)**, where **antiphospholipid antibodies (aPL)** bind to complexes involving plasma proteins, particularly **$eta_2$-glycoprotein I**, on the endothelial surface.- This binding activates and injures the endothelium, leading to the expression of pro-coagulant factors and adhesive molecules, resulting in a systemic shift toward **thrombosis**.*Platelet activation*- While aPL antibodies do cause platelet activation and aggregation, this effect is often considered downstream or secondary to the primary interaction the antibodies have with **endothelial cells** and plasma proteins.- aPL antibodies binding to platelets via **$eta_2$-glycoprotein I** enhances the production of thromboxane A2 and promotes thrombus stabilization.*Protein C deficiency*- This is typically an inherited disorder causing decreased levels or function of the key anticoagulant Protein C, a mechanism distinct from **autoimmunity**.- Although aPL antibodies can sometimes interfere with Protein C and S function indirectly, the underlying mechanism generating the thrombotic state remains **endothelial activation**.*Factor V Leiden mutation*- This is the most common inherited thrombophilia, leading to resistance to activated **Protein C** degradation of Factor Va and VIIIa.- This inherited defect is separate from the acquired, autoimmune mechanism responsible for thrombosis in **Antiphospholipid Syndrome**.*Hyperhomocysteinemia*- Elevated **homocysteine** levels create a prothrombotic state primarily via direct cytotoxicity and oxidative stress to the **vascular endothelium**.- This condition is an independent risk factor for thrombosis and is not the pathognomonic mechanism of acquired thrombophilia defined by **lupus anticoagulant** and **anticardiolipin antibodies**.
Crystal arthropathies UK Medical PG Question 5: A 61-year-old man presents with progressive weakness in his hands and difficulty swallowing. EMG shows myopathic changes. Muscle biopsy shows rimmed vacuoles and eosinophilic inclusions. What is the most likely diagnosis?
- A. Polymyositis
- B. Dermatomyositis
- C. Inclusion body myositis (Correct Answer)
- D. Myasthenia gravis
- E. Muscular dystrophy
Crystal arthropathies Explanation: ***Inclusion body myositis*** - The combination of **progressive distal weakness** (hands) and **dysphagia**, particularly in an older man, is highly characteristic. - Definitive diagnosis relies on muscle biopsy findings of **rimmed vacuoles** and **eosinophilic inclusions**, as well as **myopathic changes** on EMG. *Polymyositis* - Typically presents with **proximal muscle weakness**, affecting hips and shoulders, rather than predominant distal hand weakness or prominent dysphagia. - Muscle biopsy shows **endomysial inflammatory infiltrates** but lacks the characteristic rimmed vacuoles or inclusions seen in IBM. *Dermatomyositis* - Shares **proximal muscle weakness** with polymyositis but is uniquely identified by specific **cutaneous manifestations** like heliotrope rash and Gottron's papules, which are not mentioned. - Muscle biopsy shows **perifascicular atrophy** and perimysial inflammation, differing from IBM's distinctive pathology. *Myasthenia gravis* - A **neuromuscular junction disorder** causing fluctuating weakness that worsens with activity, often affecting ocular, bulbar, and limb muscles. - EMG would show a **decremental response** on repetitive nerve stimulation, not primary myopathic changes, and muscle biopsy would be normal. *Muscular dystrophy* - A broad category of **genetic muscle diseases** that cause progressive weakness and myopathic changes, but the specific biopsy findings of rimmed vacuoles and eosinophilic inclusions are not typical. - Different types of muscular dystrophy have distinct genetic causes and biopsy findings (e.g., dystrophin absence in Duchenne) that do not match the features presented.
Crystal arthropathies UK Medical PG Question 6: A 52-year-old woman presents with progressive dysphagia and weight loss. She has tight skin on her face and hands. ANA shows nucleolar pattern. What is the most concerning complication to screen for?
- A. Renal crisis
- B. Pulmonary hypertension (Correct Answer)
- C. Cardiac involvement
- D. Esophageal stricture
- E. Digital ulceration
Crystal arthropathies Explanation: ***Pulmonary hypertension*** - This patient's presentation (tight skin on face/hands, dysphagia, nucleolar ANA pattern) strongly suggests **Systemic Sclerosis (SSc)**, likely the limited cutaneous form. - **Pulmonary arterial hypertension (PAH)** is a leading cause of mortality in SSc, particularly associated with the nucleolar ANA pattern (often linked to anti-U3 RNP/fibrillarin antibodies), requiring regular screening with **echocardiograms**. *Renal crisis* - **Scleroderma Renal Crisis (SRC)** involves acute onset of **malignant hypertension** and rapid kidney failure. - SRC is more commonly associated with **diffuse cutaneous SSc** and **Anti-RNA Polymerase III antibodies**, rather than the nucleolar ANA pattern. *Cardiac involvement* - Direct **cardiac involvement** (e.g., myocarditis, pericarditis, conduction defects) can occur in SSc. - While serious, **pulmonary hypertension** is statistically the most common and acutely life-threatening cardiopulmonary complication in SSc patients, making it the priority for routine screening. *Esophageal stricture* - **Dysphagia** and weight loss are highly suggestive of **esophageal dysmotility**, a nearly universal finding in SSc. - While **esophageal strictures** can occur from chronic reflux in SSc, they are a local complication, not the most concerning *systemic* or *life-threatening* complication requiring primary screening compared to PAH. *Digital ulceration* - **Digital ulcerations** are caused by severe **Raynaud's phenomenon** and microvascular ischemia, leading to pain and potential tissue loss. - Though causing significant morbidity, digital ulcerations are a peripheral manifestation and not the most acutely life-threatening *systemic* complication requiring broad mortality screening compared to **pulmonary hypertension**.
Crystal arthropathies UK Medical PG Question 7: A 41-year-old woman presents with recurrent episodes of severe abdominal pain and confusion. During attacks, her urine turns dark red. She has a family history of similar symptoms. What is the most appropriate acute treatment?
- A. High-carbohydrate diet
- B. Hemin therapy
- C. Avoid precipitating drugs
- D. IV fluids and analgesia
- E. All of the above (Correct Answer)
Crystal arthropathies Explanation: ***All of the above***
- The clinical presentation (severe abdominal pain, confusion, dark urine, and family history) is highly suggestive of an acute **porphyria attack**, such as **Acute Intermittent Porphyria (AIP)**.
- Acute management requires a multifaceted approach, encompassing **hemin therapy**, **high-carbohydrate diet**, **avoidance of precipitating drugs**, and **supportive care** with IV fluids and analgesia.
*High-carbohydrate diet*
- Administering a high-dose **glucose (dextrose)** intravenously is crucial as a high carbohydrate load represses the activity of **$\delta$-aminolevulinic acid (ALA) synthase**, thereby reducing the production of neurotoxic porphyrin precursors.
- This therapy is often initiated promptly for all acute attacks, especially mild ones, and while awaiting the preparation or administration of **hemin therapy**.
*Hemin therapy*
- **Hemin (or hematin)** is considered the most specific and definitive treatment for a severe acute attack, as it directly suppresses hepatic **$\delta$-aminolevulinic acid (ALA) synthase** through negative feedback.
- Early initiation of intravenous hemin significantly shortens the duration of the attack and helps prevent or mitigate **neurological damage**.
*Avoid precipitating drugs*
- Many medications (e.g., barbiturates, sulfa drugs, some antiepileptics) are potent **inducers of cytochrome P450 enzymes**, which in turn accelerate the production of porphyrin precursors, worsening the attack.
- Rapidly identifying and discontinuing all porphyrinogenic agents is mandatory to halt the exacerbation and reduce the accumulation of neurotoxic intermediaries like **ALA** and **porphobilinogen**.
*IV fluids and analgesia*
- Severe abdominal pain, often disproportionate to physical findings, is a hallmark of acute porphyria and necessitates potent **opioid analgesics** (e.g., morphine) for effective pain management.
- Patients are frequently volume-depleted, requiring **IV fluid resuscitation**, and may also need correction of **electrolyte derangements**, such as **hyponatremia** and **hypomagnesemia**, often associated with SIADH.
Crystal arthropathies UK Medical PG Question 8: A 32-year-old woman presents with recurrent miscarriages and livedo reticularis. Blood tests show thrombocytopenia and prolonged APTT. What is the most likely diagnosis?
- A. Systemic lupus erythematosus
- B. Antiphospholipid syndrome (Correct Answer)
- C. Thrombotic thrombocytopenic purpura
- D. Factor V Leiden
- E. Protein S deficiency
Crystal arthropathies Explanation: ***Antiphospholipid syndrome***
Crystal arthropathies UK Medical PG Question 9: A 38-year-old woman presents with fatigue and palpitations. Blood tests show Hb 6.8 g/dL, MCV 68 fL, ferritin 5 µg/L. She has heavy menstrual periods. What is the most appropriate initial treatment?
- A. Blood transfusion
- B. Oral iron (Correct Answer)
- C. IV iron
- D. Gynecological referral
- E. Endoscopy
Crystal arthropathies Explanation: ***Oral iron*** - Oral iron supplementation is the **first-line** and preferred treatment for iron deficiency anemia in stable patients due to its effectiveness, safety, and low cost.- The laboratory findings (Hb 6.8 g/dL, MCV 68 fL, ferritin 5 µg/L) confirm severe **microcytic anemia** due to iron deficiency, which replacement therapy directly targets.*Blood transfusion* - Transfusion is generally reserved for patients with severe symptomatic anemia causing **hemodynamic instability** or those who fail to respond rapidly to iron therapy.- Though Hb is low (6.8 g/dL), stable patients with chronic IDA typically respond adequately and safely to iron supplementation alone.*IV iron* - Intravenous iron is typically reserved for cases of **oral iron intolerance**, documented **malabsorption**, or in specific conditions necessitating rapid correction (e.g., late pregnancy, CKD).- Unless there is a clinical reason preventing oral intake or absorption, it is not the initial standard treatment for uncomplicated IDA.*Gynecological referral* - While essential to manage the underlying cause (**heavy menstrual bleeding** or HMB), addressing the etiology is secondary to initiating treatment for the severe nutritional deficiency.- HMB is the likely cause of the iron depletion, and the referral should follow the initiation of IDA treatment.*Endoscopy* - GI investigation (endoscopy/colonoscopy) is the standard workup for IDA in men, or in postmenopausal women, where GI bleeding is the most likely source.- In a premenopausal woman with heavy menstrual periods, the cause is adequately explained by gynecological loss, making GI workup unnecessary as the initial step.
Crystal arthropathies UK Medical PG Question 10: A 48-year-old woman presents with progressive muscle weakness and skin rash over her knuckles. CK is elevated. She's concerned about cancer risk. What percentage have associated malignancy?
- A. <5%
- B. 10-15%
- C. 20-30% (Correct Answer)
- D. 40-50%
- E. >60%
Crystal arthropathies Explanation: ***20-30%***- The risk of **internal malignancy** in adult patients with **dermatomyositis (DM)** is estimated to be around 15% to 30%, warranting age-appropriate cancer screening.- DM is considered a classic **paraneoplastic syndrome**, often preceding or occurring concurrently with various cancers like ovarian, lung, pancreatic, or gastric cancer.*<5%*- This range significantly **underestimates** the actual malignancy risk associated with adult-onset dermatomyositis.- This percentage is closer to the risk observed in **juvenile dermatomyositis**, which has a much lower association with cancer.*10-15%*- While this range represents a significant risk, it is often cited as the *minimum* risk and **does not capture** the higher prevalence found in specialized studies, particularly in older patients.- This may be closer to the risk for **polymyositis**, which generally has a weaker association with malignancy than dermatomyositis.*40-50%*- This range is considered **too high** for the overall prevalence of associated malignancy in DM.- Although the risk is elevated, the **majority** of adult dermatomyositis cases are not solely paraneoplastic syndrome related.*>60%*- This is a **highly exaggerated** estimate; the majority of patients diagnosed with dermatomyositis **do not** have an underlying malignancy.- A percentage this high would suggest that cancer is almost an **obligate finding**, which is clinically inaccurate.
More Crystal arthropathies UK Medical PG questions available in the OnCourse app. Practice MCQs, flashcards, and get detailed explanations.
