Infection is an important cause of morbidity and mortality in immunocompromised patients. The high risk of infection is not only the consequence of the underlying disease but also the result of the diagnostic, monitoring and therapeutic procedures performed on these patients. Infections may be exogenous or endogenous in origin. The prevention of exogenous infections requires a high standard of hygiene. As many infections are acquired in hospitals, an effective control of nosocomial infection programme is crucial in preventing infections in the immunocompromised. Prevention of endogenous infections involves suppression of the aerobic bacterial flora (selective decontamination) and measures to maintain gastrointestinal epithelial integrity to reduce risk of translocation of intestinal flora. Boosting the host immunity through passive and active immunisation should also be considered. Prevention of infection in the immunocompromised is no easy task and requires a multidisciplinary approach.
Methicillin resistant Staphylococcus aureus (MRSA) is a major infection control problem in many countries. There have been many reports of outbreaks in neonatal nurseries including, in our part of the world, Australia, Hong Kong and Malaysia. A recent outbreak of MRSA in the neonatal intensive care unit in the Kandang Kerbau Hospital, Singapore, presented us with the opportunity to study the clinical characteristics of the outbreak and the effects of infection control measures. Neonates admitted to the neonatal intensive care unit were studied over a 20-month period. They were all screened for nasal colonisation on admission and weekly thereafter. Infections were documented. Over this period there were altogether 2,576 admissions of which 85 infants had nasal colonisation with MRSA (3.3%) and 28 developed infections (1%). Although the majority of infants colonised by MRSA suffered no ill effects, 3 had septicaemia and 2 had septicaemia with osteomyelitis. There were no deaths. Standard infection control measures with barrier nursing and the use of mupirocin nasal ointment were ineffective, and control was achieved only after strict cohorting together with the use of mupirocin was instituted. This was done without additional costs to the department and without additional nurses or doctors.