Successful therapy in unusual generalized Dermatophilus congolensis infection in a calf based on modified in vitro disk diffusion test

Abstract

Bovine dermatophilosis is a dermatitis characterized by typical focal or localized lesions with “paintbrush” aspect and occasionally as disseminated cutaneous disease. We report the case of a one-year-old Nelore female with history of chronic cutaneous disseminated lesions that appeared immediately after a rainfall period. Serous to purulent exudates, hair with tufted appearance, hyperkeratotic, non-pruritic, hardened, yellowish to brown, and coalescent crusty lesions were observed distributed all over its body. Removal of the crusts revealed ulcerated or hemorrhagic areas, with irregular elevated crusts like “paintbrush”. Microbiological diagnosis enabled the identification of a microorganism, the Dermatophilus congolensis. Despite disseminated and chronic lesions, we obtained a successful therapy with parenteral therapy using long-acting tetracycline based on modified in vitro disk diffusion test. The present report highlights success therapy in uncommon generalized bovine dermatophilosis with selection of first-choice drugs based on modified in vitro susceptibility test, and need of responsible use of antimicrobials in livestock.

Identification and Antimicrobial Resistance of Dermatophilus congolensis from Cattle in Saint Kitts and Nevis

“…Penicillin-streptomycin, penicillin alone, as well as amoxicillin and lincomycin-spectinomycin have also been reported to successfully treat dermatophilosis [ 3 , 4 , 18 ], although the condition was not completely cured in all cases. Suboptimal results were achieved when erythromycin was tested in sheep with dermatophilosis [ 18 ].…”

“…Genomic bacterial DNA was purified using the Qiagen Allprep bacterial DNA/RNA/protein kit (Qiagen, Hilden, Germany. The agac gene that encodes alkaline ceramide protein was amplified with the primers forward:5′-TGGCAGCTCTGATGAGTACCACAA-3′; Reverse:5′-AATG-TGCCGGGAACGGAAATCAAC-3′ to produce a 127 bp product [ 4 ]. We also assessed the capacity of MALDI-TOF MS (Brucker Daltonics, Germany), for the confirmation of D. congolensis .…”

“…Dermatophilus congolensis is a facultatively anaerobic actinomycete that can infect a wide range of animals as well as humans, leading to the skin disease dermatophilosis, also commonly referred to as mycotic dermatitis (erroneously as it is not a mycosis), rain rot, rain scald or streptotrichosis [ 1 , 2 , 3 , 4 ]. The acute form of the disease is mainly localized in the epidermis and clinically manifests as purulent, crusted and matted hair masses formed as a direct result of the pustular process [ 2 ].…”

“…The prevention of this disease is mainly achieved through management factors such as separation of the animals, sheltering the animals and protection from too much moisture if possible. In cases where the infection is widespread, treatment is necessary and antimicrobials and acaricides are used [ 3 , 4 , 9 ]. Mainly penicillin, aminoglycosides and tetracyclines are used to treat infected animals [ 4 , 9 ].…”

“…In cases where the infection is widespread, treatment is necessary and antimicrobials and acaricides are used [ 3 , 4 , 9 ]. Mainly penicillin, aminoglycosides and tetracyclines are used to treat infected animals [ 4 , 9 ]. Acquired antimicrobial resistance has not been reported to date, even though antimicrobial treatments are common.…”