Diagnosis and Antimicrobial Therapy of Lung Infiltrates in Febrile Neutropenic Cancer Patients

Abstract

Pulmonary infiltrates develop in up to 25% of febrile neutropenic patients and are frequently refractory to broad-spectrum antibacterial therapy. Etiologically, Aspergillus spp., Pneumocystis jiroveci, multi-resistant Gram-negative rods as well as mycobacteria and respiratory viruses may be involved. Taking into account the predominant role of fungal pathogens, typically without microbiological proof, prompt addition of mold-active systemic antifungal therapy improves clinical outcome, while other microorganisms should typically be targeted based upon microbiological test results only. Microbial isolates from blood cultures, bronchoalveolar lavage or respiratory secretions must be critically interpreted with respect to their etiological relevance for pulmonary infiltrates. Non-culture based diagnostic procedures to detect circulating antigens such as galactomannan or 1,3-beta-D-glucan, or PCR techniques to amplify DNA from blood, bronchoalveolar lavage or tissue specimens, may facilitate the diagnosis. For pre-emptive antifungal treatment, voriconazole or liposomal amphotericin B are preferred. Antifungal treatment should be continued for at least 14 days before non-response and treatment modification are considered. Primary choice for treatment of Pneumocystis pneumonia remains high-dose trimethoprim-sulfamethoxazole, while cytomegalovirus pneumonia is treated with ganciclovir in the majority of patients affected.

Etiology, diagnosis, and management of pneumonia in immunosuppressed patients

“…These factors, which are simply enumerated but not discussed in this review, include radiation, drug-related pulmonary toxicity, diffuse alveolar haemorrhage, pulmonary oedema, and lung lesions due to the underlying disease (e.g., leukemic infiltrates, engraftment syndrome, GVHD, lymphangitic carcinomatosis, and pulmonary vasculitis, among others). Existing guidelines for managing lung disease in critically ill immunocompromised patients emphasize the importance of obtaining valid diagnostic samples [16]. However, antimicrobial therapy is often started immediately, before samples are collected.…”

Pneumonia in the neutropenic cancer patient

“…Nonfermenting-Gram-negative bacilli (NF-GNB), such as Stenotrophomonas maltophilia , Burkholderia spp., Chryseobacterium meningosepticum , and Alcaligenes ( Achromobacter ) spp., are increasingly recognized as etiologic agents in both CAP and nosocomial pneumonias. (38–45) Streptococcus pyogenes, Neisseria meningitides , and Moraxella catarrhalis are less frequent causes of CAP. Atypical pathogens such as Mycoplasma pneumoniae , Chlamydophyla pneumoniae , and Legionella spp.…”

“…Thus, while infection remains the most frequent cause of these radiographic abnormalities in neutropenic patients,(13, 21, 22, 27, 45, 74) the potential diagnoses are numerous and the challenge is to identify those patients who are most likely to benefit from further investigations in addition to empiric antimicrobial therapy. (21, 22, 45, 74)…”

“…Such techniques include polymerase chain reaction (PCR) testing and antigen detection methods. (41, 45, 81)…”

Infections chez les patients neutropéniques

“…Dans quelques cas, rares, une bactériémie à staphylocoque à coagulase négative peut être d'origine muqueuse [16] : un délai diff érentiel de positivité des hémocultures négatif (tableau I), une colonisation de plusieurs sites à ce germe constituent alors des arguments en faveur de cette hypothèse. [18,19], la majorité des patients recevant au moment de l'examen un traitement antibiotique voire antifongique à large spectre. L'examen cytobactériologique des urines, systématique, tient compte de l'absence habituelle de leucocyturie.…”