Infections cause direct maternal morbidity and remain a leading cause of maternal morbidity in the United States and globally. In this chapter, we will discuss the physiologic considerations of infectious diseases in pregnancy, alterations in pregnancy response to infections, changes in immune cell populations, and fetal immune response. Pregnancy is a state of relative immunosuppression order for the maternal “host” to not reject fetus and this immunosuppression has consequences in the setting of infectious illness. The pathophysiology, epidemiology, obstetric management, antibiotic therapy, and anesthetic management of the most frequent bacterial and viral infections in the obstetric patient including chorioamnionitis, sepsis, human immunodeficiency virus (HIV), group A streptococcus, and TORCH infections. Additionally, we will present the obstetric and anesthetic management of uncommon bacterial, viral, and parasitic infections. This chapter provides nuanced understanding of peripartum immunologic physiology, an overview of common obstetrical infections, and a quick resource for uncommon as well as tropical infections, such as tuberculosis and malaria as they relate to pregnancy for obstetrics anesthesia providers. Management pearls included in this chapter can improve maternal and fetal outcomes for pregnant patients with infections illnesses.

Infective, granulomatous and benign histiocytic disorders are only rarely an indication for bone marrow (BM) examination and therefore often represent unexpected or incidental findings. Yet since they are frequently linked to a variety of life-threatening underlying conditions, diagnosing such disorders in the BM is almost always significant for the affected patient. This chapter summarizes and illustrates the most common disorders of this type in the BM with a special emphasis on diagnostic and differential diagnostic clues.

Infectious diseases of the lower gastrointestinal tract are caused by a vast array of viral, bacterial, fungal, and parasitic organisms. Pathologists are often called upon to distinguish infectious enterocolitis from other inflammatory disorders and, when possible, identify the causative pathogen or group of pathogens. Thus, pathologists should be aware of the patterns of injury and morphologic features that suggest infectious enterocolitides and should be able to generate a reasonable but narrow differential diagnosis that guides clinical management. This chapter reviews the clinical, gross, and, microscopic features of common and emerging infectious diseases of the lower gastrointestinal tract and emphasizes the pathologic findings that aid the appropriate classification of these diseases in daily practice.