The crucial role of molecular testing to facilitate the diagnosis of pneumocystis pneumonia during pregnancy

Pneumocystis pneumonia is an important human immunodeficiency virus (HIV)-associated opportunistic infection, and especially so in pregnant HIV-positive patients. We report a case of a 40-year-old woman in her first trimester of pregnancy who initially presented with acute gastroenteritis symptoms but due to a history of high-risk behaviour and the observation of oral thrush, she was worked up for HIV infection. Her retroviral status was positive and her CD4+ T cell count was only 8 cells/mL. She was also worked up for pneumocystis pneumonia due to the presence of mild resting tachypnoea and a notable drop in oxygen saturation (from 100% to 88%) following brief ambulation. Her chest radiograph revealed bilaterally symmetrical lower zone reticular opacities and Giemsa staining of her bronchoalveolar lavage (BAL) was negative for Pneumocystis jirovecii cysts. However, real-time P. jirovecii polymerase chain reaction (PCR) testing on the same BAL specimen revealed the presence of the organism. A course of oral co-trimoxazole plus prednisolone was commenced and her clinical condition improved.

Screening for New Delhi metallo-Beta-lactamase-1 in Enterobacteriaceae: is there a role for the modified Hodge test?

Objective: The New Delhi metallo-Beta-lactamase-1 [NDM-1] enzyme is a plasmid-encoded enzyme that inactivates carbapenem antibiotics. This study aims to ascertain if the modified Hodge test [MHT] has a role in screening for NDM-1 in Enterobacteriaceae with reduced carbapenem susceptibility

Methods: Over a period of one year, all Enterobacteriaceae isolates from all clinical specimens with reduced susceptibility to at least one carbapenem were subjected to MHT and conventional polymerase chain reaction [PCR] detection of the NDM-1 gene

Results: A total of 13,098 Enterobacteriaceae isolates were screened and 63 [0.48%] had reduced susceptibility to at least one carbapenem. Out of the 63 isolates, 45 [71.4%] were MHT-positive. The NDM-1 gene was detected in 18 of the 63 isolates [28.6%]. All 18 PCR-positive isolates were also MHT-positive. Thus, the sensitivity and specificity of the MHT in detecting NDM-1 in Enterobacteriaceae with reduced carbapenem susceptibility are 100% and 40%, respectively

Conclusion: The MHT is a useful test to screen for the presence of NDM-1 in Enterobacteriaceae with reduced carbapenem susceptibility. However, due to its rather low specificity, all MHT-positive isolates should be subjected to alternative tests [e.g. PCR] for confirmation, especially if other types of carbapenemases [e.g. KPC] are prevalent

Paecilomyces lilacinus fungaemia in an AIDS patient:the importance of mycological diagnosis

Fungaemia due to Paecilomyces lilacinus is generally not considered in AIDS patients because this condition is not categorised as an AIDS-indicator illness. We report a case of a 25-year-old lady who presented to our hospital with Guillain-Barre Syndrome, with the subsequent development of refractory fungaemia, multi-organ failure and disseminated intravascular coagulopathy. Amphotericin B was given as empirical antifungal therapy. HIV screening was reactive and Paecilomyces lilacinus was isolated from her blood. The fungaemia did not resolve after one week of amphotericin B treatment. The addition of itraconazole was also unsuccessful in clearing the fungaemia. Accurate mycological diagnosis is important in the care of AIDS patients with fungaemia because of the risk of treatment failure with empirical therapy