key: cord-0762010-yitq7xhc
authors: Headley, Selwyn Arlington; Müller, Melissa Cristina; Silva de Oliveira, Thalita Evani; Barros Gil Duarte, Caroline Ambiel; Valente Pereira, Priscilla Fajardo; Vieira, Marcos Vinícius; Cunha, Cristina Wetzel; Flores, Eduardo Furtado; Naylor Lisbôa, Júlio Augusto; Pretto-Giordano, Lucienne Garcia
title: Diphtheric aspergillosis tracheitis with gastrointestinal dissemination secondary to viral infections in a dairy calf
date: 2020-09-08
journal: Microb Pathog
DOI: 10.1016/j.micpath.2020.104497
sha: 127d8ac9ff53f85e971b8a504151c66084aba62d
doc_id: 762010
cord_uid: yitq7xhc

Diphtheric aspergillosis tracheitis is an uncommon syndrome described in human pathology, usually associated with immunosuppression in the affected individuals. Interestingly, no comparative/equivalent cases were found in domestic animals. This report describes the pathological and mycological findings associated with diphtheric aspergillosis tracheitis in an immunocompromised calf. The main pathological findings were diphtheric tracheitis and rhinitis, and necrotizing ruminitis associated with intralesional septate, acute branching fungal hyphae consistent with Aspergillus spp. Mycological culture and isolation confirmed the fungal hyphae as A. fumigatus due to characteristic features. Immunohistochemistry (IHC) assays identified intralesional antigens of bovine viral diarrhea virus (BVDV) and malignant catarrhal fever virus (MCFV) at the trachea and small intestine; IHC detected intralesional antigens of bovine alphaherpesvirus 1 (BoHV-1) only at the trachea. These findings confirmed the simultaneous occurrence of A. fumigatus with concomitant infections due to BVDV, MCFV, and BoHV-1 in this calf. Since ovine gammaherpesvirus-2 (OvHV-2) is the cause of MCF in Brail, it is likely that the intralesional MCFV antigens identified were those of OvHV-2. In this case, disseminated aspergillosis was probably associated with the undeveloped immunological status of the calf that was further impaired due to the combined immunodepressive effects of BVDV and BoHV-1 infections. Although BVDV and BoHV-1 are infectious disease pathogens frequently associated with the development of bovine respiratory disease (BRD) in feedlot and dairy cattle, the identification of intralesional OvHV-2-like antigens in several parts of the lungs suggest that this MCFV also played a role in the BRD-associated lesions identified in this calf.

antibodies were administered on FFPE tissues known to demonstrate negative immunoreactive to the primary 120 antibodies mentioned above. Negative and positive controls were included in all IHC assays. The calf arriving at the VTH-UEL was dyspenic, febrile (39.8°C), dehydrated (10%), mildly infested 134 by ticks, diarrheic with ulcerations at the tongue and oral cavity. The hematological results were within normal 135 parameters and cryptosporidiosis was not identified by routine parasitological evaluations, but fungal hyphae 136 were observed within the fecal sample, while blood gas analysis revealed acidosis. Fecal ss-PAGE analysis did 137 not identify BRA; RT-PCR assays did not amplify BVDV and BoCV RNA from the fecal samples.

Accordingly, sodium bicarbonate and lactated Ringer´s solutions were administered to control the acidosis and 139 dehydration, respectively, and antibiotic therapy with ceftiofur (2.2 mg/kg/IM/SID) was initiated. At this time,

suckling reflex was absent, and the heifer received milk via an esophageal tube. On the second day, suckling 141 reflex remained absent, the animal was in esternal recumbency during most of the day, and thus continued to 142 receive milk via esophageal tube. The calf was found dead the following day, i.e., three days after arrival at the 143 VTH-UEL.

Pathological findings

The main gross findings were observed at the respiratory and gastrointestinal systems, with restricted white-colored material that was adhered to the mucosal surface of the distal trachea, which was diagnosed as elongated, slightly elevated, foci at the ruminal mucosa (Fig. 1C) . These foci varied from 0.2 cm to 0.5 cm 152 diameter for rounded lesions; the elongated foci contained a centrally located, 1x 2cm, clear and slightly 153 depressed area, that was surrounded by an irregularly shaped hyperemic zone. There was a focally extensive 154 hyperemic region at the serosa of the colon; examination of the colonic mucosa revealed an extensive region of 155 hyperemia that contained a centrally located, irregularly or T-shaped, slightly elevated, white-cream colored 156 plaque that was adhered to the mucosal surface (Fig. 1D ). The lesions observed at the mucosal surfaces of the 157 rumen and colon were interpreted as mycotic related, with consequent gross diagnoses of fungal rumenitis and 158 colitis, respectively.

Histopathologic alterations were severe at the respiratory and gastrointestinal system, with restricted There was prompt fungal growth at 37℃. Grossly, the fungal colony on the SDA medium was blue 202 green in color with an externally located white rim and of velvety texture (Fig 5A-B) ; the reverse colony was 203 cream colored ( Fig 5C) . Microscopically, the stipes were long, smooth walled; vesicles were dome-shaped with 204 uniserate conidial heads and dispersed conidia, measuring 2.1-2.5 µm in diameter (Fig. 5D) 

it is likely that the antigens identified were OvHV-2, but since molecular testing was not performed, we shall 224 refer to this as MCFV-associated disease.

The gross and histopathologic findings observed at the tracheal confirmed a diagnosis of diphtheritic 226 fungal tracheitis due to A. fumigatus; similar findings were not identified in ruminants nor in domestic animals. 

Aspergillus and 321 aspergilloses in wild and domestic animals: a global health concern with parallels to human disease

Aspergillus fumigatus and aspergillosis

Gastrointestinal aspergillosis and zygomycosis of cattle

Fungi associated with bovine abortion in the northern plains states (USA)

Mycotic abortion in cattle

Survey of bovine mycotic 334 mastitis in dairy herds in the State of Sao Paulo, Brazil

Aspergillus fumigatus and Aspergillosis in 2019

Aspergillus 338 tracheobronchitis: report of 8 cases and review of the literature

Tracheobronchial manifestations of Aspergillus infections

The authors are extremely grateful to Ms Eliana Pereira for the technical assistance in the preparation of all 312 mycological analyses. This study forms part of an agreement between DMVP/UEL and ARS/USDA (58-2090-