Invasive aspergillosis in leukemic children

Aspergillus flavus: an emerging non-fumigatus Aspergillus species of significance

Invasive aspergillosis is rare in immunocompetent people but contributes to significant morbidity and mortality in immunosuppressed patients. The majority (approximately 80%) of invasive Aspergillus infections is caused by Aspergillus fumigatus. The second most frequent (approximately 15-20%) pathogenic species is Aspergillus flavus and to a lesser extent, Aspergillus niger and Aspergillus terreus. Aspergillus flavus has emerged as a predominant pathogen in patients with fungal sinusitis and fungal keratitis in several institutions worldwide. To date, there has not been any publication exclusively reviewing the topic of A. flavus in the literature. This article reviews the microbiology, toxigenicity and epidemiology of A. flavus as well as describes the clinical characteristics, diagnosis and management of infections caused by this organism.

Invasive aspergillosis in cancer

Ten confirmed cases of invasive aspergillosis (IA) in cancer patients were analysed retrospectively. Eight were pulmonary, one was sinonasal and one was cutaneous. The majority of patients had haematological malignancies (7), the remaining three were cases of solid tumours. Fever was present in all 10 cases. Cough and lung signs were present in all eight cases of invasive pulmonary aspergillosis. Haemoptysis was encountered in three of nine cases of pulmonary and sinonasal aspergillosis. Mortality was low (2%). While corticosteroids, antibiotics and anticancer chemotherapy/radiotherapy were factors predisposing the patients to IA, neutropenia was perhaps responsible for their mortality. Seven of the patients had other associated pathogens isolated in culture in addition to Aspergillus spp. Aspergillus fumigatus was the predominant species, followed by A. flavus, A. glaucus, A. nidulans and A. niger. Direct microscopic examination (in six of seven cases) and culture (six of seven cases) correlated well with radiographic and clinical findings in cases with lung involvement. Serology for anti-Aspergillus antibodies performed by gel diffusion precipitin test was positive in one case of sinonasal aspergillosis, wherein only one precipitin band was observed. Correlation of clinical symptoms, consistent radiographic findings and microbiological work-up (the latter including a triad of direct microscopy, culture and serology) are required to arrive at a diagnosis of IA, especially where histology cannot form the mainstay of diagnosis.

Sequestration of the alveolar bone by invasive aspergillosis in acute myeloid leukemia

Compared to non-invasive aspergillosis, invasive aspergillosis in the region of the mouth, jaw and face has rarely been reported. It occurs particularly often in the presence of haematological oncological illness. The case of a patient suffering from acute myeloid leukemia is described; he contracted invasive aspergillosis of the lungs and the alveolar processes in the course of chemotherapeutic treatment. All the alveolar processes in the region of the premolars and molars were demarcated and had to be removed by sequestrectomy. The therapy of invasive aspergillosis should be carried out within the framework of intensive interdisciplinary treatment. In addition to systemic and local antimycotic therapy, the debridement of necrotic hard and soft tissue was necessary.

Invasive aspergillosis in human immunodeficiency virus-infected children

BACKGROUND

Aspergillosis is an uncommon yet serious opportunistic infection in patients with AIDS. It has been extensively reported in HIV-infected adult patients. To our knowledge there are no studies that describe the epidemiology, clinical manifestations and outcome of aspergillosis in a large HIV-infected pediatric population.

METHODS

We reviewed the records of all 473 HIV-infected children followed in the Pediatric Branch of the National Cancer Institute for 9 years from 1987 through 1995 for the presence of Aspergillus infection.

RESULTS

Seven (1.5%) patients developed invasive aspergillosis during the study period. All patients had low CD4 counts reflecting severe immunosuppression. Sustained neutropenia (> 7 days) or corticosteroid therapy as a predisposing factor for invasive aspergillosis was encountered in only two patients (28%). Invasive pulmonary aspergillosis developed in five patients and cutaneous aspergillosis in two. The most common presenting features in patients with pulmonary aspergillosis were fever, cough and dyspnea. Patients with cutaneous aspergillosis were diagnosed during life and successfully treated with amphotericin B and surgery, whereas diagnosis of pulmonary aspergillosis was made clinically in only one patient.

CONCLUSIONS

Aspergillosis is an uncommon but highly lethal opportunistic infection in HIV-infected children. Invasive pulmonary aspergillosis should be considered in the differential diagnosis in febrile, HIV-infected children with persistent pulmonary infiltrates.

Urokinase in the treatment of bacteremia and candidemia in patients with right atrial catheters

BACKGROUND

Urokinase plasminogen activator was used in combination with antibiotic therapy given through the catheter to improve the treatment of right atrial catheter infections.

METHODS

One hundred fifty-four episodes of bacteremia and candidemia occurring in 97 children with malignant or hematologic conditions were treated. After 24 hours of antibiotic therapy, 1 ml urokinase (5000 units/ml) was instilled, dwelling 1 hour, and then removed; this was repeated within 24 hours. Antibiotic therapy was continued for then removed; this was repeated within 24 hours. Antibiotic therapy was continued for 10 to 35 days. Administration of urokinase was repeated once if infection recurred within 8 weeks of initial treatment.

RESULTS

There were no adverse affects from administration of urokinase. Bacteremia clearance failed after initial administration of urokinase in 12 episodes; this failure was mostly associated with the presence of gram-positive organisms. Blood culture results remained positive in three cases after repeat therapy. Bacteremia recurred in 15 of 125 episodes; in three cases bacteremia did not clear after repeat administration of urokinase or recurred again. Recurrence was lowest for gram-negative organisms and Candida sp. Less than 5% of catheters were removed as a result of treatment failure.

CONCLUSIONS

Administration of urokinase combined with antibiotic therapy is safe and may be effective in treating bacteremia and candidemia in patients with right atrial catheters. Use of urokinase may improve treatment of organisms that are otherwise difficult to control and may prevent recurrence of infection.