A male infant, age 22 months, reached the intensive care unit in septic shock following a 3-day illness of diarrhea and vomiting (with fever for 2 days). Despite vigorous resuscitative efforts that...

A male infant, age 22 months, reached the intensive care unit in septic shock following a 3-day illness of diarrhea and vomiting (with fever for 2 days). Despite vigorous resuscitative efforts that included antibiotics, ventilation, fluid resuscitation, vasopressin, and corticosteroids, the child died six hours after admission. Streptococcus pneumoniae was isolated from antemortem blood cultures. An autopsy revealed that the patient had only vestigial splenic tissue. Questions 1.Explain why the absence of a spleen would contribute to bacteremia (presence of bacteria in the blood). 2.Asplenia can be diagnosed by ultrasound or by doing a blood smear. The microscopic observation of odd-shaped erythrocytes is indicative of asplenia. Explain why. 3.Would the patient described above be able to mount an immune response to early-childhood vaccines (measles, diphtheria, pertussis, etc.), which are injected subcutaneously? Explain. 4.Give one reason why the patient’s condition might not have been detected during the first year of life. 5.Blood tests showed that the patient had normal levels of antibodies. How is it possible for an asplenic individual to have normal levels of immunoglobulin?