Which condition is indicated by a lack of surfactant in the lungs of infants?

A lack of surfactant in the lungs of infants is a hallmark of Respiratory Distress Syndrome (RDS), particularly in premature infants. Surfactant is a substance that reduces surface tension in the alveoli, the tiny air sacs in the lungs, and helps keep them open for gas exchange. When there is insufficient surfactant, the alveoli collapse, leading to difficulty in breathing, decreased lung compliance, and inadequate oxygenation of the blood. This condition is often seen in newborns who are born before 34 weeks of gestation or in those who may have been delivered with complications that affect lung maturity.

In contrast, the other conditions listed are unrelated to surfactant deficiency. For instance, bronchogenic carcinoma pertains to cancer of the lungs, cystic fibrosis is a genetic disorder affecting the lungs and digestive system due to thick mucus, and pulmonary infarction involves tissue death in the lungs due to a lack of blood supply. These conditions have distinct underlying mechanisms and clinical presentations that do not involve surfactant levels.