A hospitalized man with anemia and hemoglobinuria undergoes hematologic work-up. His reticulocyte count is elevated. Other lab results are pending. Which of the following diagnoses is most consistent with the information available thus far?

A 17-year-old girl complains of fatigue and "difficulty concentrating in school". She recently began to feel her heart beating in her chest. Physical exam finds pale mucosal membranes. Her peripheral blood smear reveals hypochromic, microcytic red cells. Which of the following laboratory test findings is most likely to be present in this girl?

An healthy-looking term baby girl born to a mother with no prenatal care presents with uncontrolled bleeding from the umbilical cord stump. This finding suggests a deficiency of which of the following coagulation factors?

A child with cystic fibrosis presents with signs of a bleeding diathesis. Deficiency in which of the following factors is the most likely the cause of this child's coagulopathy?

A 5-year-old child presents with a sudden onset of bloody diarrhea, vomiting of blood, and renal failure. Fever and neurologic symptoms are not seen in the child. His BUN is markedly elevated, but blood clotting times and fibrin degradation product levels are normal. His peripheral blood exam shows poikilocytes, schistocytes, and decreased number of platelets. What is the most likely etiology of this child's condition?

A 19-year-old primigravida gives birth at 35 weeks age of gestation to a markedly hydropic male infant. The infant's hematocrit is 17%, and numerous nucleated red cells and few erythroblasts are seen in his peripheral blood. Which of the following is the most likely mechanism of the infant's condition?

Which one of the following parasitic diseases would most likely be associated with a normal hemoglobin and hematocrit?

A patient with low serum haptoglobin concentration and increased urine hemosiderin most likely has which of the following disorders?

A woman delivers a stillborn boy at 31 week’s gestation. Examination of the boy shows severe generalized edema and ascites with hepatosplenomegaly. Lab exam shows that this boy had thalassemia. Which one of the following is the most likely genotype?

For two weeks, a 35-year-old man has complained of purpura and bleeding of the gums. Physical exam finds him pale and his temperature is 39˚C. This clinical picture is compatible with which of the following disorders?

An HIV-positive, 39-year-old woman is suspected of having a B-cell lymphoma. Which one of the following pathologic findings would be most likely in this patient?

A patient has a lymphoproliferative disorder containing mature B cells that mark weakly with kappa light chain on plasma membrane, strongly with CD5, strongly with CD23, and weakly with CD22. Which one of the following is the most likely diagnosis?

A radioactive tracer dye is injected subcutaneously into the forearm of an experimental subject. What is the first area of the first draining lymph node that would develop significant radioactivity?

A bone marrow biopsy is done for staging of a non-Hodgkin lymphoma. Histologic examination shows a focal paratrabecular pattern of marrow involvement. This pattern is most consistent with which of the following lymphomas?

A 28-year-old woman presents with a neck mass. She “rarely gets sick” and only goes to her doctor annually for a routine check-up. Her temperature reads 38.1ºC. Physical exam finds a 2.3-cm non-tender cervical lymph node. Excisional lymph node biopsy would most likely reveal:

Biopsy taken from 15-year-old boy's para-aortic lymph nodes reveal a diffuse architecture, medium-sized non-cleaved neoplastic lymphocytes, and “tingible-body” macrophages. Some lymphocytes exhibit vacuolated cytoplasm and fat stains are positive. You would expect the tumor cells to exhibit a:

A lymph node biopsy of a 6-year-old boy shows markedly decreased numbers of lymphocytes in the paracortical areas. Analysis of his peripheral blood leukocytes is likely to reveal normal to elevated numbers of cells expressing surface:

A second-year medical student plans to determine which forms of cancer can theoretically be prevented by a vaccine targeted against an oncogenic virus. Which one of the following diseases might be prevented by such a vaccine?

A lower jaw mass excised from an African adolescent man is sent to surgical pathology. Microscopic exam shows intermediate-sized lymphocytes with amphophilic cytoplasm and round nuclei with small nucleoli. Mitotic figures are numerous. The Ki-67 proliferation index is close to a 100%. Which one of the following markers would be negative in this tumor?