Loose connective tissue — MCQs

A 55-year-old female presents with pain in both hands and wrists for the past several years. It is associated with morning stiffness that lasts for almost an hour. Physical examination reveals tenderness and swelling in both hands and wrists, most severe over the proximal interphalangeal joints. Laboratory investigation reveals the presence of anti-cyclic citrullinated peptide (anti-CCP). Which of the following immune-mediated injuries is responsible for this patient’s condition?

A 30-year-old man comes to the physician for a follow-up examination 1 month after sustaining a chemical burn over the dorsum of his right hand and forearm. Physical examination shows hyperextension of the hand at the wrist. The skin over the dorsum of the wrist is tense and there is a thick, epithelialized scar. Range of motion of the right wrist is restricted. This patient's contracture is most likely due to activity of which of the following cells?

A 15-year-old boy presents with shortness of breath on exertion for the past 2 weeks. Although he does not have any other complaints, he is concerned about not gaining much weight despite a good appetite. His height is 188 cm (6 ft 2 in) and weight is 58 kg (124 lb). His blood pressure is 134/56 mm Hg and his pulse rate is 78/min. On cardiac auscultation, his apex beat is displaced laterally with a diastolic murmur lateral to the left sternal border. Slit-lamp examination shows an upward and outward displacement of both lenses. Synthesis of which of the following proteins is most likely defective in this patient?

A 48-year-old man is brought to the emergency department with a stab wound to his chest. The wound is treated in the emergency room. Three months later he develops a firm 4 x 3 cm nodular mass with intact epithelium over the site of the chest wound. On local examination, the scar is firm, non-tender, and there is no erythema. The mass is excised and microscopic examination reveals fibroblasts with plentiful collagen. Which of the following processes is most likely related to the series of events mentioned above?

In a routine medical examination, a young man is noted to be tall with slight scoliosis and pectus excavatum. He had been told that he was over the 95% percentile for height as a child. Auscultation reveals a heart murmur, and transthoracic echocardiography shows an enlarged aortic root and mitral valve prolapse. Blood screening for fibrillin-1 (FBN1) gene mutation is positive and plasma homocysteine is normal. This patient is at high risk for which of the following complications?

An investigator is studying the interaction between epithelial cells and calcium ion concentration. When the calcium ion concentration available to a sample of epithelial tissue is decreased, an increased gap between adjacent epithelial cells is seen on electron microscopy. This observed decrease in cell adhesion is most likely due to an effect on which of the following proteins?

An 8-year old boy is brought into clinic for evaluation of possible scoliosis that was newly found on a routine exam at school. On exam, he is also noted to be in the 99th percentile for height and 70th percentile for weight. He appears to have abnormally long extremities as well as an upward lens dislocation on ophthalmologic exam. A mutation leading to a defect in which of the following proteins is the most likely cause of his condition?

A 37-year-old man presents to the clinic because of painful, severe blistering over his buttocks for the past week. About a year ago, he noticed a similar outbreak on his inner thighs, but it receded within a few days on its own. Physical examination shows the blisters are tense, and rubbing the affected skin does not result in ‘popping’ of the blisters. A biopsy shows the entire epidermis lifting away from the basal lamina with extensive inflammatory infiltrates abundant with eosinophils. Immunofluorescence shows a linear pattern of immune complex deposits. Which of the following cellular structures, if defective, is most likely involved in the formation of these blisters?

A 31-year-old woman scrapes her finger on an exposed nail and sustains a minor laceration. Five minutes later, her finger is red, swollen, and painful. She has no past medical history and does not take any medications. She drinks socially with her friends and does not smoke. The inflammatory cell type most likely to be prominent in this patient's finger has which of the following characteristics?

A 25-year-old man presents to the emergency department with sudden-onset severe pain in the right shoulder that occurred when he threw a bowling ball 2 hours ago. He has a history of dislocations in both shoulders and subluxation of the right knee and left wrist. There is no history of fractures. On physical examination, the right arm is slightly abducted and externally rotated. An anterior bulge is seen near the shoulder joint. The neurovascular examination of the right arm shows no abnormalities. The skin examination shows multiple widened atrophic scars around the knees, elbows, and ankles. The skin of the neck and around the elbow can easily be extended up to 4 cm. The sclera is white. The remainder of the physical examination shows no abnormalities. A defect in which of the following proteins is the most likely cause of the findings in this patient?