A 3-year-old boy is brought to the dermatology clinic by his parents due to blistering skin lesions and scarring on sun-exposed areas. The parents report that these symptoms have been present since infancy and worsen with sun exposure. The child also has hypertrichosis, dark reddish-brown discoloration of the teeth, and a history of pink-stained diapers. Physical examination reveals vesicles, bullae, erosions, crusting, and hyperpigmented scars on the face and hands. Laboratory studies show hemolytic anemia and hepatosplenomegaly. Which of the following is the most likely diagnosis?

Patient: 13-month-old boy Presenting Complaint: High fever and rash History: The boy’s mother reports that her son had a high fever (up to 39.5°C) for the past 4 days. Despite the fever, he remained active and playful, with no significant cough, vomiting, or diarrhea. This morning, the fever resolved abruptly, but she noticed a pink, non-itchy rash on his chest, back, and abdomen. The rash has started spreading to his neck and arms. There is no history of recent vaccinations or travel. The child has had normal developmental milestones and no significant past medical history. Physical Examination: General appearance: Alert and interactive Vital signs: Afebrile, normal respiratory and heart rate Skin: Maculopapular, blanching rash over the trunk and neck, spreading peripherally Head and neck: No lymphadenopathy, no conjunctivitis Neurological: No focal deficits or signs of meningitis Respiratory and abdominal exams: Normal What is the most likely diagnosis for this child?

A 60-year-old woman with known CREST syndrome reports worsening difficulty swallowing over the past year. She also mentions that she has noticed lumps under the skin of her hands. What is the most likely explanation for the lumps under the skin in this patient?

A 50-year-old male patient comes in with complaints of skin changes on his fingers and frequent episodes of Raynaud’s phenomenon. His blood work shows the presence of anticentromere antibodies. Which of the following symptoms is most closely associated with the “R” in CREST syndrome?

A 45-year-old woman presents to your clinic with complaints of Raynaud’s phenomenon, difficulty swallowing, and skin tightening over her fingers. On examination, you note telangiectasias on her face and hands. Which of the following is NOT typically associated with CREST syndrome?

A 48-year-old woman with CREST syndrome presents with persistent heartburn, difficulty swallowing, and worsening Raynaud’s phenomenon. She has no signs of interstitial lung disease or pulmonary hypertension. What is the most appropriate initial treatment for her esophageal symptoms?

A 60-year-old woman with a history of CREST syndrome presents with worsening shortness of breath and fatigue. She denies any fever or recent infections. A chest CT shows no pulmonary fibrosis, but echocardiography reveals increased pulmonary arterial pressure. What is the underlying mechanism responsible for this patient’s worsening symptoms?

A 10-year-old boy with no significant past medical history is brought to the emergency department after eating shrimp at a restaurant. Within minutes, he developed swelling of the lips, hives on his chest and arms, and difficulty breathing. His parents state that he also complained of a “tight throat” and dizziness. On physical examination, he has facial edema, audible stridor, and hypotension (BP: 80/50 mmHg). What is the most appropriate immediate treatment?

A 32-year-old woman presents to the emergency department with symptoms and signs suggestive of serum sickness two weeks after being treated with infliximab for Crohn’s disease. Which of the following is the most likely set of clinical findings associated with serum sickness?

A 30-year-old man presents with fever, rash, and joint pain 9 days after receiving a tetanus antitoxin following a wound injury. He has no history of allergies. Laboratory tests reveal proteinuria and hematuria. Which of the following is the most appropriate initial treatment for this patient?