Detection of invasive pulmonary aspergillosis in mice using lung perfusion single-photon emission computed tomography with [99mTc]MAA.

There is an urgent need for development of better diagnostic strategies to improve outcomes in patients with invasive pulmonary aspergillosis (IPA). We hypothesized that lung perfusion single-photon emission computed tomography (SPECT) may be more sensitive and specific than computed tomography (CT) of the chest for detection of IPA because it is an angioinvasive pulmonary infection with characteristics that are different from those of bacterial pneumonia. We used SPECT with injection of technetium-99m-labeled macroaggregated albumin ([99mTc]MAA) to measure pulmonary perfusion in noninfected mice, mice with IPA, and mice with bacterial pneumonia. Histopathologic analysis was performed to evaluate the correlation between the perfusion defect and mould invasion. We also attempted to quantitatively evaluate the SPECT images to identify differences in decreased perfusion levels in affected areas in the mouse lung. Histopathologic analysis in the IPA mouse model showed a clear match between areas with a perfusion defect and the presence of mold, indicating that the location of the perfusion defect on a SPECT image reflects angioinvasion of the mould in the lungs. Some of these perfusion defects could be seen before appearance of the infiltrate of CT images. Quantitative analysis confirmed that perfusion in the affected areas was significantly decreased in the IPA model but not in the bacterial pneumonia model (P < .0001). This imaging method may be preferable to the alternative methods presently used to identify the presence of mold in a patient's lungs.

Characteristics of azole-resistant Aspergillus fumigatus attached to agricultural products imported to Japan.

Due to the increase in the number of azole-resistant Aspergillus fumigatus, there is an urgent need of data to predict future trends and prevent further spreading. The intercountry transfer of resistant A. fumigatus on plant bulbs have been reported. We investigated existence and characteristics of resistant isolates attached to agricultural products imported to Japan. We purchased 292 samples in Japan. All samples were screened for the existence of azole-resistant A. fumigatus. For positive isolates, minimum inhibitory concentrations of the drugs were determined. We also analyzed Cyp51A, Hmg1, and Erg6 mutations of these isolates and conducted microsatellite genotyping. Fourteen azole-resistant isolates were detected, of which 13 were cultured from flower bulbs imported from the Netherlands. Among them 5 were from 11 bulbs of Hippeastrum (45.5%), 5 were from 24 bulbs of Gladiolus (20.8%), 2 were from 4 bulbs of Ixia (50.0%), and 1 was from 22 bulbs of Tulipa (4.5%). Only 1 resistant isolate was cultured from the 10 bulbs of Narcissus (10.0%) originating in Japan. Various novel mutations including Y121F/T289A in Cyp51A with no tandem repeat in promoter region were discovered from imported strains. Our study provides important data showing that agricultural imports provide a possible route for their intercontinental spread and raises the concern that strains harboring highly diverse Cyp51A mutations might increase in clinical settings in the future.

[A case report of Kimura's disease causing visual dysfunction with remarkable eyelid swelling].

PURPOSE: We report a case of Kimura's disease involving the eyelids, presenting with bilateral eyelid swelling so severe that the eyelids could not be opened. CASE: A 37-year-old man presented with eyelid swelling and was unable to open both eyelids. He noted swelling and mass of bilateral eyelids since a year previously, and the masses enlarged gradually impairing eye-opening. Hard soft elastic tumors were palpated in both eyelids. Blood examination revealed marked peripheral blood eosinophilia and an increased serum IgE level. On T 1-weighted MR images, the tumors were observed as isointense masses compared to the extraocular muscles. On T 2-weighted images, the tumors showed hypointense signals while some parts were hyperintense compared to the extraocular muscles. On Gd-enhanced T 1-weighted images, the tumors demonstrated marked enhancement. The tumors in both eyelids were extirpated en bloc. Histopathology of the tumors demonstrated many lymphoid follicles and infiltration of large numbers of eosinophils and lymphocytes. Eosinophilic abscess and proliferation of blood capillaries were observed between the lymphoid follicles. These findings led to a diagnosis of Kimura's disease. PCR revealed clonal rearrangement of the T cell receptor gene. CONCLUSION: Kimura's disease may cause remarkable eyelid swelling and lead to visual dysfunction. Since recurrence of Kimura's disease is known to be associated with clonal rearrangement of T cell receptor genes, similar cases should be followed carefully for recurrence.

Correlation between high-resolution optical coherence tomography (OCT) images and histopathology in an N-methyl-N-nitrosourea-induced retinal degeneration rat model.

BACKGROUND: Recent research on macular diseases has prompted investigations into the condition of the intersection between the inner and outer segments (IS/OS), and its relationship with retinal photoreceptor abnormalities. Because the correlation between optical coherence tomography (OCT) images and histopathology is unclear, the authors compared them in an N-methyl-N-nitrosourea (MNU)-induced photoreceptor degeneration rat model. METHODS: MNU (60 mg/kg), which is toxic to photoreceptors, was injected in 12 Brown Norway rats. After MNU administration, three rats were used per histopathological study 3 h, 6 h, 24 h and 1 week after the injections. Two healthy rats served as controls. OCT images were taken before euthanisation. RESULTS: 3 h after the MNU injections, the IS and OS were oedematous, but the IS/OS borderline was recognised histopathologically, and the IS/OS was depicted on the OCT images. Six hours after injections, the OS were preserved, but the IS structures were destroyed or partially disorganised histopathologically, and the IS/OS was not observed on the OCT images. Twenty-four hours after the injections, the IS and OS were totally disorganised histopathologically, and the IS/OS was not depicted on the OCT images. CONCLUSION: The IS structure might be the origin of the IS/OS on OCT images.