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ENARE practice questions

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Question 1Residência Médica

A 24-year-old woman has a 3-day history of dysuria, urinary frequency, and suprapubic discomfort, with no fever or flank pain. Urinalysis shows pyuria and a positive nitrite test. What is the most appropriate initial management?

  1. Renal ultrasound before any antibiotic
  2. Observation without antibiotics for 48 hours
  3. Intravenous ceftriaxone followed by admission
  4. Oral nitrofurantoin for 5 days Correct answer.

Explanation

Acute uncomplicated cystitis in a non-pregnant woman is treated with a short oral course of an agent that concentrates in urine, such as nitrofurantoin. The absence of fever and flank pain argues against pyelonephritis, so parenteral therapy and admission are unnecessary. Imaging is not indicated in a first uncomplicated episode.

Question 2Residência Médica

Which electrolyte disturbance is most characteristically associated with prolonged vomiting from gastric outlet obstruction?

  1. Hyperkalemia with respiratory alkalosis
  2. Hypernatremia with metabolic acidosis
  3. Hyperkalemia with metabolic acidosis
  4. Hypokalemia with metabolic alkalosis Correct answer.

Explanation

Loss of gastric hydrochloric acid produces a metabolic alkalosis, and volume depletion drives renal potassium wasting, leading to hypokalemia. The classic pattern is hypokalemic, hypochloremic metabolic alkalosis.

Question 3Residência Médica

A 62-year-old man with chronic obstructive pulmonary disease has a resting oxygen saturation of 86% on room air. Which target is appropriate for long-term home oxygen therapy?

  1. Maintain saturation above 99%
  2. Maintain saturation between 88% and 92% Correct answer.
  3. Use oxygen only during sleep
  4. Maintain saturation between 70% and 80%

Explanation

In patients at risk of hypercapnia, oxygen is titrated to a saturation of roughly 88% to 92% to avoid worsening carbon dioxide retention while correcting hypoxemia. Overcorrection can blunt the hypoxic ventilatory drive and worsen gas exchange.

Question 4Residência Médica

A patient presents with sudden painless loss of vision in one eye described as a curtain descending over the visual field. Which diagnosis must be excluded first?

  1. Acute angle-closure glaucoma
  2. Optic neuritis
  3. Retinal detachment Correct answer.
  4. Central retinal artery occlusion

Explanation

A painless curtain-like visual field defect is the classic presentation of rhegmatogenous retinal detachment, which is a sight-threatening emergency requiring prompt ophthalmologic evaluation. The description of a shade or curtain is the key discriminator.

Question 5Residência Médica

Which finding on a peripheral blood smear most strongly suggests that a microcytic anemia is due to iron deficiency rather than thalassemia trait?

  1. Presence of nucleated red cells
  2. Target cells
  3. Basophilic stippling
  4. Increased red cell distribution width Correct answer.

Explanation

Iron deficiency produces anisocytosis with a raised red cell distribution width, whereas thalassemia trait typically shows uniform microcytosis with a normal red cell distribution width. The Mentzer index can further help distinguish the two.

Question 6Residência Médica

A 55-year-old man has crushing substernal chest pain. The electrocardiogram shows ST elevation in leads II, III, and aVF. Which coronary artery is most likely occluded?

  1. Left main coronary artery
  2. Left circumflex artery
  3. Left anterior descending artery
  4. Right coronary artery Correct answer.

Explanation

ST elevation in the inferior leads II, III, and aVF localizes the infarct to the inferior wall, most often supplied by the right coronary artery. Reciprocal depression in aVL supports this localization.

Question 7Residência Médica

A 30-year-old woman is admitted with diabetic ketoacidosis. After initial fluid resuscitation, which electrolyte must be monitored most closely because insulin therapy can cause a precipitous fall?

  1. Calcium
  2. Phosphorus
  3. Magnesium
  4. Potassium Correct answer.

Explanation

Insulin drives potassium intracellularly, so serum potassium can drop rapidly during treatment of ketoacidosis. Potassium is replaced once levels fall below the upper reference range and renal function is adequate.

Question 8Residência Médica

A previously healthy 8-year-old child develops fever, sore throat, and a fine sandpaper-like rash with circumoral pallor. Which finding on examination would best confirm the suspected diagnosis?

  1. Koplik spots on the buccal mucosa
  2. Vesicles on an erythematous base along the dermatome
  3. Strawberry tongue with desquamation of the fingertips Correct answer.
  4. Conjunctival injection with coryza

Explanation

The combination of fever, pharyngitis, sandpaper rash, and circumoral pallor suggests scarlet fever. A strawberry tongue and subsequent desquamation support group A streptococcal infection.

Question 9Residência Médica

Which parameter is the most reliable early indicator of effective chest compressions during cardiopulmonary resuscitation in an intubated patient?

  1. End-tidal carbon dioxide Correct answer.
  2. Urine output
  3. Pupillary light reflex
  4. Central venous pressure

Explanation

End-tidal carbon dioxide reflects pulmonary blood flow generated by compressions, so a rising value indicates improved cardiac output. Values persistently below 10 mmHg suggest ineffective resuscitation.

Question 10Residência Médica

A 70-year-old woman has a serum sodium of 118 mEq/L after several days of worsening confusion. She is asymptomatic neurologically apart from mild lethargy. What is the most appropriate initial approach?

  1. Rapid correction with hypertonic saline to reach 135 mEq/L within 6 hours
  2. Immediate hemodialysis
  3. Free water restriction alone with no monitoring
  4. Slow correction with a target rise of 8 to 10 mEq/L in 24 hours Correct answer.

Explanation

Chronic hyponatremia must be corrected slowly to avoid osmotic demyelination, generally limiting the rise to 8 to 10 mEq/L in the first 24 hours. Hypertonic saline is reserved for severe symptomatic cases such as seizures.

Question 11Residência Médica

A newborn is noted to have a harsh systolic murmur and cyanosis that does not improve with supplemental oxygen. Which mechanism best explains the persistent hypoxemia?

  1. Intracardiac right-to-left shunting Correct answer.
  2. Left ventricular outflow obstruction
  3. Diffuse alveolar collapse
  4. Increased pulmonary blood flow

Explanation

Cyanotic congenital heart disease with a right-to-left shunt delivers desaturated blood to the systemic circulation, producing hypoxemia refractory to oxygen. The Eisenmenger physiology or tetralogy physiology explains the fixed shunt.

Question 12Residência Médica

Which clinical feature most strongly distinguishes an exudative pleural effusion from a transudative one?

  1. Presence of dyspnea
  2. Pleural fluid protein to serum protein ratio above 0.5 Correct answer.
  3. Unilateral distribution
  4. Radiographic blunting of the costophrenic angle

Explanation

The Light criteria classify an effusion as exudative when the pleural fluid to serum protein ratio exceeds 0.5, or the pleural fluid to serum lactate dehydrogenase ratio exceeds 0.6, or the fluid lactate dehydrogenase exceeds two-thirds of the upper normal serum value. These ratios reflect increased capillary permeability.

Question 13Residência Médica

A 45-year-old man presents with colicky right flank pain radiating to the groin and visible hematuria. Non-contrast computed tomography confirms a 6 mm distal ureteral stone. Which management is most appropriate?

  1. Observation with analgesia and hydration Correct answer.
  2. Immediate open ureterolithotomy
  3. Long-term indwelling stent placement without follow-up
  4. Percutaneous nephrostomy

Explanation

Distal ureteral stones smaller than 10 mm often pass spontaneously, so initial management is analgesia, hydration, and follow-up. Medical expulsive therapy may be considered for distal stones.

Question 14Residência Médica

A 28-year-old woman has a 2-week history of palpitations, heat intolerance, weight loss, and tremor. Thyroid function tests show a suppressed thyroid-stimulating hormone and elevated free thyroxine. Which finding on examination is most consistent with this diagnosis?

  1. Periorbital edema with dry coarse skin
  2. Delayed relaxation phase of deep tendon reflexes
  3. Bradycardia with cold intolerance
  4. Diffuse goiter with a systolic flow murmur Correct answer.

Explanation

Hyperthyroidism causes a hypermetabolic state with tachycardia, warm skin, tremor, and a diffuse goiter with an audible flow murmur from increased glandular vascularity.

Question 15Residência Médica

A 68-year-old woman has a distal radius fracture after a fall from standing height. Which underlying condition should be investigated as a contributing cause?

  1. Osteoporosis Correct answer.
  2. Scurvy
  3. Paget disease of the skull
  4. Osteopetrosis

Explanation

A fragility fracture from a standing-height fall in an older adult is a hallmark of osteoporosis and warrants evaluation with bone densitometry and assessment of secondary causes. Fragility fractures define clinically significant osteoporosis.

Question 16Residência Médica

A patient with cirrhosis and ascites undergoes diagnostic paracentesis. The serum-ascites albumin gradient is 1.5 g/dL. What does this value indicate?

  1. Exudative peritoneal carcinomatosis
  2. Tuberculous peritonitis
  3. Portal hypertension as the cause of ascites Correct answer.
  4. Pancreatic ascites

Explanation

A serum-ascites albumin gradient of 1.1 g/dL or greater indicates portal hypertension as the mechanism, most commonly cirrhosis. Gradients below 1.1 g/dL point to peritoneal causes such as malignancy or tuberculosis.

Question 17Residência Médica

Which vaccine is contraindicated in a patient with severe combined immunodeficiency?

  1. Inactivated influenza vaccine
  2. Hepatitis B recombinant vaccine
  3. Tetanus toxoid
  4. Live attenuated measles-mumps-rubella vaccine Correct answer.

Explanation

Live attenuated vaccines are contraindicated in severe immunodeficiency because replication of the attenuated organism can cause disseminated disease. Inactivated and subunit vaccines are generally safe.

Question 18Residência Médica

A 24-year-old man is brought in after a seizure. He has a history of alcohol use and his last drink was 36 hours ago. Which medication is first-line for prevention of further withdrawal seizures and delirium tremens?

  1. Benzodiazepines Correct answer.
  2. Propranolol
  3. Haloperidol
  4. Diphenhydramine

Explanation

Benzodiazepines are the cornerstone of treatment for alcohol withdrawal because they restore inhibitory GABA activity and prevent seizures and delirium tremens. They are titrated to symptom-triggered scales.

Question 19Residência Médica

A 3-year-old child presents with a barking cough, inspiratory stridor, and hoarseness following a mild upper respiratory infection. What is the most likely diagnosis?

  1. Croup Correct answer.
  2. Bronchiolitis
  3. Foreign body aspiration
  4. Epiglottitis

Explanation

Croup, or acute laryngotracheobronchitis, presents with a barking cough, hoarseness, and inspiratory stridor after a viral prodrome. It is most common in children between 6 months and 3 years of age.

Question 20Residência Médica

A 60-year-old man has progressive dyspnea, dry cough, and fine bibasilar crackles. High-resolution computed tomography shows subpleural honeycombing. Which diagnosis is most likely?

  1. Pulmonary embolism
  2. Asthma
  3. Idiopathic pulmonary fibrosis Correct answer.
  4. Chronic obstructive pulmonary disease

Explanation

Progressive dyspnea with bibasilar crackles and honeycombing on high-resolution computed tomography is characteristic of idiopathic pulmonary fibrosis, a chronic fibrosing interstitial pneumonia.

Question 21Residência Médica

A patient with major depressive disorder is started on a selective serotonin reuptake inhibitor. Which statement about the expected time course of therapeutic response is correct?

  1. The drug should be stopped if no effect occurs at 3 days
  2. Therapeutic response is unrelated to duration of treatment
  3. Improvement in sleep and appetite may precede mood improvement by weeks Correct answer.
  4. Full benefit is typically seen within 24 hours

Explanation

Antidepressants often improve sleep, appetite, and energy before mood lifts, with full antidepressant effect typically taking 4 to 6 weeks. This early phase requires monitoring for suicidal ideation as energy returns.

Question 22Residência Médica

A 72-year-old man has sudden painless monocular visual loss lasting minutes, described as a gray shade over the eye. Which underlying condition should be investigated most urgently?

  1. Open-angle glaucoma
  2. Vitreous hemorrhage
  3. Macular hole
  4. Carotid artery stenosis Correct answer.

Explanation

Transient monocular visual loss, or amaurosis fugax, suggests embolic ischemia from ipsilateral carotid disease or a cardiac source. It is a warning sign for stroke and requires urgent vascular evaluation.

Question 23Residência Médica

A 35-year-old woman presents with fever, a malar rash, arthralgia, and a positive antinuclear antibody test. Which additional laboratory finding would most specifically support systemic lupus erythematosus?

  1. Rheumatoid factor
  2. Anti-histone antibodies
  3. Anti-double-stranded DNA antibodies Correct answer.
  4. Antimitochondrial antibodies

Explanation

Anti-double-stranded DNA antibodies are highly specific for systemic lupus erythematosus and correlate with disease activity and nephritis risk. Anti-Smith antibodies are also specific but less sensitive.

Question 24Residência Médica

A 55-year-old man with a history of nephrolithiasis has severe epigastric pain radiating to the back with elevated lipase. Which electrolyte abnormality is most likely to occur as a complication of severe acute pancreatitis?

  1. Hyperkalemia
  2. Hypocalcemia Correct answer.
  3. Hypernatremia
  4. Hypercalcemia

Explanation

Severe pancreatitis causes saponification of calcium in peripancreatic fat, leading to hypocalcemia, which is a marker of severity. Calcium should be monitored and replaced if symptomatic.

Question 25Residência Médica

A 4-week-old infant is brought in with projectile nonbilious vomiting after feeds and a palpable olive-shaped mass in the epigastrium. Which metabolic derangement is expected?

  1. Metabolic acidosis with hyperkalemia
  2. Normal acid-base status with hyperglycemia
  3. Respiratory alkalosis with hypernatremia
  4. Hypochloremic hypokalemic metabolic alkalosis Correct answer.

Explanation

Hypertrophic pyloric stenosis causes loss of gastric hydrochloric acid and potassium, producing a hypochloremic, hypokalemic metabolic alkalosis with paradoxic aciduria. Correction of volume and electrolytes precedes surgery.

Question 26Residência Médica

A 62-year-old man with chronic obstructive pulmonary disease presents with increased sputum purulence, increased sputum volume, and worsening dyspnea. He is hemodynamically stable and has no signs of respiratory failure. Which is the most appropriate initial management?

  1. Intravenous thrombolysis
  2. Inhaled short-acting bronchodilators plus systemic corticosteroids and antibiotics Correct answer.
  3. Urgent endotracheal intubation
  4. Immediate noninvasive positive-pressure ventilation

Explanation

A COPD exacerbation with all three cardinal symptoms (dyspnea, sputum volume, sputum purulence) warrants bronchodilators, a short course of systemic corticosteroids, and antibiotics. Noninvasive ventilation and intubation are reserved for respiratory failure or acidosis, not for stable patients.

Question 27Residência Médica

Which finding on urinalysis most suggests a nephritic rather than a nephrotic process?

  1. Marked proteinuria with oval fat bodies
  2. Broad waxy casts
  3. Urinary eosinophils
  4. Dysmorphic red blood cells with red blood cell casts Correct answer.

Explanation

Glomerular inflammation in nephritic syndromes produces hematuria with dysmorphic red cells and red blood cell casts. Oval fat bodies and heavy proteinuria reflect nephrotic-range podocyte injury, and waxy casts indicate chronic renal failure.

Question 28Residência Médica

A 26-year-old woman has recurrent episodes of severe abdominal pain, tachycardia, and anxiety. During an attack her urine turns dark on standing. Which test is most appropriate to confirm the diagnosis?

  1. Serum cortisol after dexamethasone suppression
  2. Measurement of urine porphobilinogen Correct answer.
  3. Serum tryptase
  4. Plasma metanephrines

Explanation

Acute intermittent porphyria presents with neurovisceral attacks and dark urine due to porphyrin precursors; elevated urinary porphobilinogen during an attack is diagnostic. Metanephrines assess pheochromocytoma and tryptase assesses mast cell disorders.

Question 29Residência Médica

A 6-month-old infant has a febrile illness followed by generalized seizures. Which cerebrospinal fluid finding most supports a diagnosis of bacterial rather than viral meningitis?

  1. Neutrophilic pleocytosis with low glucose and high protein Correct answer.
  2. Normal cell count with mildly elevated protein
  3. Xanthochromia with elevated opening pressure
  4. Lymphocytic pleocytosis with normal glucose

Explanation

Bacterial meningitis typically produces a neutrophilic pleocytosis with low glucose and elevated protein. Viral meningitis usually shows lymphocytic pleocytosis with normal glucose, and xanthochromia suggests subarachnoid hemorrhage.

Question 30Residência Médica

A 34-year-old woman has fatigue, weight gain, cold intolerance, and a diffusely enlarged, firm goiter. Thyroid-stimulating hormone is elevated and free thyroxine is low. Which antibody is most likely to be positive?

  1. Anti-thyroid peroxidase antibody Correct answer.
  2. Anti-double-stranded DNA antibody
  3. Anti-transglutaminase antibody
  4. Anti-acetylcholine receptor antibody

Explanation

Hashimoto thyroiditis is the most common cause of primary hypothyroidism in iodine-sufficient regions and is characterized by anti-thyroid peroxidase antibodies. The other antibodies are associated with myasthenia gravis, systemic lupus erythematosus, and celiac disease.

Question 31Residência Médica

A 58-year-old man has a chronic nonproductive cough, weight loss, and a chest radiograph showing a right upper lobe cavitary lesion with hilar lymphadenopathy. Which is the most appropriate next step?

  1. Begin high-dose corticosteroids
  2. Start empiric broad-spectrum antibiotics for community-acquired pneumonia
  3. Collect sputum for acid-fast bacilli smear and culture Correct answer.
  4. Order a ventilation-perfusion scan

Explanation

Upper lobe cavitation with chronic symptoms suggests pulmonary tuberculosis, and sputum acid-fast bacilli smear and culture are the diagnostic standard. Antibiotics for typical pneumonia, ventilation-perfusion scanning, and steroids would not establish or treat this diagnosis.

Question 32Residência Médica

A 68-year-old man has a resting tremor, bradykinesia, rigidity, and postural instability. Which medication is most appropriate to initiate for his motor symptoms?

  1. Metoclopramide
  2. Haloperidol
  3. Amitriptyline
  4. Levodopa combined with carbidopa Correct answer.

Explanation

Levodopa with carbidopa is the most effective dopaminergic therapy for motor symptoms of Parkinson disease; carbidopa prevents peripheral decarboxylation and reduces nausea. Dopamine-blocking drugs such as haloperidol and metoclopramide can worsen parkinsonism.

Question 33Residência Médica

A patient is admitted with severe acute pancreatitis. Which finding is the most reliable indicator of severe disease on admission?

  1. Presence of gallstones on ultrasound
  2. Absence of vomiting
  3. Persistent organ failure lasting more than 48 hours Correct answer.
  4. Serum amylase greater than three times the upper limit of normal

Explanation

Persistent organ failure beyond 48 hours defines severe acute pancreatitis and predicts mortality. Amylase elevation and gallstone presence establish the diagnosis and cause but do not grade severity.

Question 34Residência Médica

A 24-year-old woman has a 3-day history of dysuria, urinary frequency, and suprapubic discomfort without fever or flank pain. Which is the most appropriate treatment?

  1. Oral fluconazole
  2. Intravenous vancomycin
  3. Oral nitrofurantoin Correct answer.
  4. Observation without antibiotics

Explanation

Uncomplicated cystitis is best treated with a short oral course of an agent such as nitrofurantoin. Vancomycin is reserved for resistant systemic infections, fluconazole treats candidiasis, and untreated cystitis risks progression.

Question 35Residência Médica

A 19-year-old college student has a sore throat, fever, and posterior cervical lymphadenopathy. A heterophile antibody test is positive. Which complication is most characteristic of this infection?

  1. Reye syndrome
  2. Splenic rupture Correct answer.
  3. Erythema migrans
  4. Aplastic crisis in the patient himself

Explanation

Infectious mononucleosis from Epstein-Barr virus can cause splenomegaly and splenic rupture, so contact sports should be avoided. Aplastic crisis typically occurs in patients with underlying hemolytic anemia, Reye syndrome follows aspirin use in viral illness in children, and erythema migrans indicates Lyme disease.

Question 36Residência Médica

A 47-year-old man has sudden onset of severe tearing chest pain radiating to the back. Blood pressure is 190/100 mmHg in the right arm and 150/85 mmHg in the left arm. Which is the most appropriate initial diagnostic test?

  1. D-dimer assay
  2. Exercise stress testing
  3. Troponin measurement
  4. Contrast-enhanced computed tomography of the aorta Correct answer.

Explanation

Asymmetric arm pressures with tearing pain suggest aortic dissection, and contrast-enhanced computed tomography of the aorta is the preferred diagnostic study in a stable patient. Troponin evaluates myocardial infarction, and stress testing is contraindicated in suspected dissection.

Question 37Residência Médica

A 5-year-old child is brought in with periorbital edema, and urine dipstick shows 4+ protein but no blood. Serum albumin is low and cholesterol is elevated. Which is the most likely diagnosis?

  1. Minimal change disease Correct answer.
  2. Hemolytic uremic syndrome
  3. IgA nephropathy
  4. Acute post-streptococcal glomerulonephritis

Explanation

Nephrotic-range proteinuria, hypoalbuminemia, and hyperlipidemia in a child strongly suggest minimal change disease, which is the most common childhood nephrotic syndrome. The other options are nephritic or thrombotic processes with hematuria or anemia.

Question 38Residência Médica

Which electrolyte disturbance is most commonly seen in a patient with primary hyperaldosteronism?

  1. Hypokalemia with metabolic alkalosis Correct answer.
  2. Hypernatremia with hyperchloremic acidosis
  3. Hypocalcemia with prolonged QT
  4. Hyperkalemia with metabolic acidosis

Explanation

Aldosterone excess promotes renal sodium retention and potassium excretion, producing hypokalemia and metabolic alkalosis. Hyperkalemia with acidosis is the opposite pattern, typical of hypoaldosteronism.

Question 39Residência Médica

A 30-year-old woman has a painful genital ulcer with a clean base and tender inguinal lymphadenopathy. Which organism is the most likely cause?

  1. Herpes simplex virus type 2
  2. Human papillomavirus
  3. Treponema pallidum
  4. Haemophilus ducreyi Correct answer.

Explanation

Chancroid, caused by Haemophilus ducreyi, produces a painful ulcer with a ragged base and tender regional adenopathy. Syphilis usually causes a painless chancre, herpes causes grouped vesicles, and HPV causes warts.

Question 40Residência Médica

A 65-year-old woman has a hip fracture after a low-energy fall. Which finding best indicates that her bone fragility is due to osteoporosis rather than osteomalacia?

  1. Low bone mineral density with normal serum calcium, phosphate, and alkaline phosphatase Correct answer.
  2. Looser zones on radiographs
  3. Low serum phosphate with elevated alkaline phosphatase
  4. Elevated parathyroid hormone with low calcium after vitamin D deficiency

Explanation

Osteoporosis produces reduced bone mass with normal mineral metabolism laboratory values. Osteomalacia typically shows abnormal calcium, phosphate, or alkaline phosphatase and may show Looser zones.

Question 41Residência Médica

A 52-year-old man has a painless testicular mass. Which tumor marker is most useful for following a nonseminomatous germ cell tumor?

  1. Prostate-specific antigen
  2. Alpha-fetoprotein Correct answer.
  3. CA 19-9
  4. Carcinoembryonic antigen

Explanation

Alpha-fetoprotein, often together with beta-human chorionic gonadotropin, is used to monitor nonseminomatous germ cell tumors. CEA, CA 19-9, and PSA are markers of colorectal, pancreatic, and prostatic disease respectively.

Question 42Residência Médica

A 40-year-old woman has episodic headache, palpitations, sweating, and severe hypertension. Which test is the most appropriate initial screen for the suspected diagnosis?

  1. Serum cortisol
  2. Serum thyrotropin
  3. Plasma renin activity
  4. Plasma free metanephrines Correct answer.

Explanation

Paroxysmal headache, palpitations, diaphoresis, and hypertension suggest pheochromocytoma, for which plasma free metanephrines are the most sensitive initial test. Cortisol, thyrotropin, and renin assess other endocrine causes of hypertension.

Question 43Residência Médica

A 70-year-old man has chronic kidney disease with an estimated glomerular filtration rate of 25 mL/min/1.73 m². Which metabolic abnormality is most characteristic of this stage?

  1. Metabolic alkalosis with hypokalemia
  2. Hypophosphatemia with low parathyroid hormone
  3. Hypercalcemia with suppressed parathyroid hormone
  4. Hyperphosphatemia with secondary hyperparathyroidism Correct answer.

Explanation

Declining renal phosphate excretion in chronic kidney disease causes hyperphosphatemia, which lowers ionized calcium and stimulates parathyroid hormone secretion. Hypophosphatemia and suppressed parathyroid hormone are the opposite of this pattern.

Question 44Residência Médica

A 22-year-old man has an acute asthma exacerbation with diffuse wheezing and an oxygen saturation of 92% on room air. Which medication should be given first?

  1. Inhaled long-acting beta-2 agonist
  2. Oral theophylline
  3. Oral montelukast
  4. Inhaled short-acting beta-2 agonist Correct answer.

Explanation

Inhaled short-acting beta-2 agonists are the first-line rescue therapy for acute bronchospasm because of rapid onset. Long-acting agents are maintenance-only, and montelukast and theophylline have no role in acute rescue.

Question 45Residência Médica

A 45-year-old woman has fatigue, arthralgia, and hyperpigmentation of the skin. Which laboratory finding would best support primary adrenal insufficiency?

  1. Elevated aldosterone with suppressed renin
  2. Low cortisol with elevated adrenocorticotropic hormone Correct answer.
  3. Low cortisol with low adrenocorticotropic hormone after pituitary infarction
  4. High cortisol with suppressed adrenocorticotropic hormone

Explanation

Primary adrenal failure removes cortisol feedback, so adrenocorticotropic hormone rises while cortisol is low. Hyperpigmentation results from elevated ACTH. Low ACTH with low cortisol points to secondary adrenal insufficiency.

Question 46Residência Médica

A 55-year-old man has a 6-month history of progressive dysphagia, first to solids and then to liquids, with weight loss. Which is the most appropriate initial diagnostic study?

  1. Esophageal manometry
  2. Upper endoscopy with biopsy Correct answer.
  3. Barium swallow alone
  4. Twenty-four-hour pH monitoring

Explanation

Progressive dysphagia with weight loss raises concern for esophageal malignancy, and upper endoscopy with biopsy allows direct visualization and tissue diagnosis. Manometry and pH monitoring evaluate motility and reflux, not obstructive lesions.

Question 47Residência Médica

A 28-year-old woman has a first episode of major depression with insomnia and poor appetite. Which class of antidepressant is generally preferred as first-line therapy?

  1. Selective serotonin reuptake inhibitors Correct answer.
  2. Barbiturates
  3. Monoamine oxidase inhibitors
  4. Tricyclic antidepressants

Explanation

Selective serotonin reuptake inhibitors are first-line because of favorable safety and tolerability. Monoamine oxidase inhibitors and tricyclics are reserved for refractory cases due to dietary and cardiac risks, and barbiturates are not antidepressants.

Question 48Residência Médica

A 60-year-old man with atrial fibrillation has a CHA2DS2-VASc score of 4. Which therapy is most appropriate for stroke prevention?

  1. No antithrombotic therapy
  2. Anticoagulation with a direct oral anticoagulant Correct answer.
  3. Clopidogrel monotherapy
  4. Aspirin monotherapy

Explanation

A CHA2DS2-VASc score of 2 or more in men warrants oral anticoagulation, and direct oral anticoagulants are preferred over warfarin in nonvalvular atrial fibrillation. Antiplatelet monotherapy is inadequate for this level of stroke risk.

Question 49Residência Médica

A 3-day-old newborn has not passed meconium and has progressive abdominal distension. Which diagnosis should be suspected first?

  1. Intussusception
  2. Pyloric stenosis
  3. Hirschsprung disease Correct answer.
  4. Meckel diverticulum

Explanation

Failure to pass meconium within the first 48 hours with abdominal distension suggests Hirschsprung disease, caused by aganglionic distal colon. Pyloric stenosis causes vomiting, intussusception occurs later, and Meckel diverticulum usually presents with painless bleeding.

Question 50Residência Médica

A 68-year-old man has acute gouty arthritis of the first metatarsophalangeal joint. He has a history of peptic ulcer disease and stage 4 chronic kidney disease. Which agent is the most appropriate treatment?

  1. Colchicine at full dose
  2. Intra-articular glucocorticoid injection Correct answer.
  3. High-dose oral ibuprofen
  4. Indomethacin

Explanation

Intra-articular glucocorticoids provide local anti-inflammatory control without systemic NSAID or colchicine toxicity, which is important with renal impairment and ulcer history. Nonsteroidal anti-inflammatory drugs are relatively contraindicated in advanced chronic kidney disease and peptic ulcer disease.