Lymphoid tissue histology — MCQs

A 24-year-old man, an information technology professional, gets himself tested for serum immunoglobulin M (IgM) levels because he wants to know more about his immunity. He knows that IgM levels reflect the status of his immunity, based on the internet. Although the laboratory report is normal, he consults a physician. The physician discusses human immunity and its important components. He also tells him that most circulating IgM antibodies in the blood of normal persons are produced by a specific type of B cell, which is present mostly in the peritoneal cavity and in mucosal tissues. He also mentions that these cells are components of innate immunity. Which of the following types of B cells is the physician referring to?

A 24-year-old male with cystic fibrosis is brought to the emergency room by his mother after he had difficulty breathing. He previously received a lung transplant 6 months ago and was able to recover quickly from the operation. He is compliant with all of his medications and had been doing well with no major complaints until 2 weeks ago when he began to experience shortness of breath. Exam reveals a decreased FEV1/FVC ratio and biopsy reveals lymphocytic infiltration. Which of the following components is present in the airway zone characteristically affected by the most likely cause of this patient's symptoms?

A 26-year-old woman presents to your clinic with complaints of increasing muscle fatigue that worsens after periods of sustained activity. She also reports both ptosis and diplopia that make reading in the late afternoon and evenings difficult. An edrophonium test is performed and is positive, demonstrating resolution of the patient's weakness. One organ in particular, when abnormal, is associated with this patient's condition. Which of the following embryologic structures gives rise to this organ?

A 32-year-old man comes to the physician because of a 3-week history of cough, weight loss, and night sweats. He migrated from Sri Lanka 6 months ago. He appears emaciated. His temperature is 38.1°C (100.5°F). Physical examination shows enlargement of the right supraclavicular lymph node. Chest and abdominal examination show no abnormalities. An interferon-gamma assay is positive. A biopsy specimen of the cervical lymph node is most likely to show the causal organism in which of the following locations?

A 2-year-old boy is brought to the emergency department because of fever, cough, and ear pain over the past 2 days. He has had recurrent respiratory tract infections and several episodes of giardiasis and viral gastroenteritis since he was 6 months of age. Examination shows decreased breath sounds over both lung fields and bilateral purulent otorrhea. His palatine tonsils and adenoids are hypoplastic. Quantitative flow cytometry of his blood shows decreased levels of cells that express CD19, CD20, and CD21. Which of the following is the most likely cause of this patient's condition?

A 67-year-old woman comes to the physician because of a 3-week history of fatigue and worsening back and abdominal pain. During this period, she has also had excessive night sweats and a 4.6-kg (10-lb) weight loss. She has had swelling of the neck for 3 days. She does not smoke or drink alcohol. Vital signs are within normal limits. Physical examination shows a 4-cm, supraclavicular, nontender, enlarged and fixed lymph node. The spleen is palpated 2 cm below the left costal margin. Laboratory studies show: Hemoglobin 10.4 g/dL Mean corpuscular volume 87 μm3 Leukocyte count 5,200/mm3 Platelet count 190,000/mm3 Serum Lactate dehydrogenase 310 U/L A CT scan of the thorax and abdomen shows massively enlarged paraaortic, axillary, mediastinal, and cervical lymph nodes. Histopathologic examination of an excised cervical lymph node shows lymphocytes with a high proliferative index that stain positive for CD20. Which of the following is the most likely diagnosis?

A 38-year-old man comes to the clinic complaining of recurrent abdominal pain for the past 2 months. He reports a gnawing, dull pain at the epigastric region that improves with oral ingestion. He has been taking calcium carbonate for the past few weeks; he claims that “it used to help a lot but it’s losing its effects now.” Laboratory testing demonstrated increased gastrin levels after the administration of secretin. A push endoscopy visualized several ulcers at the duodenum and proximal jejunum. What characteristics distinguish the jejunum from the duodenum?

A 23-year-old woman presents to her primary care physician with 3 days of fatigue and back pain after she started a drug for malaria prophylaxis. She says that her urine has also been darker over the same time period. Her past medical history is significant for allergies as well as a broken elbow that was treated in a cast 10 years ago. She does not take any medications, does not smoke, and drinks socially. Peripheral blood smear reveals both red blood cells with dark intracellular inclusions as well as abnormally shaped red blood cells. The immune cells responsible for the shape of these red blood cells are located in which of the following places?

A 32-year-old woman presents with amenorrhea and galactorrhea. MRI shows a pituitary adenoma. Histological examination of the surgical specimen shows cells arranged in cords and nests with sinusoidal capillaries. Special staining reveals three distinct cell types: chromophobes (50%), acidophils (40%), and basophils (10%). Immunohistochemistry shows the tumor cells staining strongly for prolactin. Evaluate the relationship between normal pituitary architecture and tumor development to determine which cell type most likely gave rise to this neoplasm.

A 65-year-old man with progressive shortness of breath undergoes transbronchial biopsy. Microscopy shows thickened alveolar septa with increased collagen deposition. Type I pneumocytes are decreased, and there is proliferation of type II pneumocytes. Alveolar macrophages are present. The patient has a history of environmental asbestos exposure 30 years ago. Evaluate the histological progression and synthesize the most likely diagnosis considering the temporal relationship and cellular changes.