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Wood colonizing fungi are specialists that exploit the lignocellulose of cell wall components in host wood cylinders as a carbon sources. Some of these specialized fungi, including Fomitiporia mediterranea (Fmed) and Phaeomoniella chlamydospora (Pch), cause the disease Esca of grapevine. This disease complex includes grapevine leaf stripe disease (GLSD) of canopies and white rot and black wood streaking in trunks. The present study gained insights into the activity of Esca pathogens in host xylem of the trunk tissues at an anatomical level. Lesions with white rot and brown wood streaking were microscopically analyzed, and the structures of affected tissues were compared with intact xylem. In trunks with white rot, demarcation zones separated intact tissues from the lesions. Immediately adjacent to the demarcation zones, cell wall decomposition initiated in the xylem. At this initial stage, cavities appeared in the secondary cell walls of libriform fibres, which expanded and closely resembled the degradation pattern of soft rot. In the advanced stage, the fibre cell walls were completely decomposed, and the vessels were attacked with a degradation pattern similar to white rot. Only remnants of the xylem elements remained, forming amorphous matrices. These decomposition patterns occurred in field samples and in wood cores artificially infected with Fmed. The obvious compartmentalization of the tissue affected by Fmed indicated a defense reaction in the xylem, according to the CODIT model. In contrast, brown wood streaking affected only small groups of vessels, adjacent libriform fibres and parenchyma. Dark inclusions in cells and tyloses in vessels indicate a defense reaction against the pathogens causing brown wood streaking. Artificial inoculation of sterile wood cores with Pch confirmed the contribution of this pathogen to brown wood streaking. This research provides insights into the structural and functional anatomy of intact and infected tissues of grapevines, which clarify the etiology of Esca, and provide new knowledge for developing new approaches to control of this disease complex.

Climate changes have promoted an increased fungal infection of maple trees with Cryptostroma corticale, the causative agent of sooty bark disease. The hosts of C. corticale are maples, and since the early 2000s the fungus has been appearing more frequently in European forests, due to the droughts and hot summers of recent years. Infestation by C. corticale discolors the wood and makes it unusable for further processing, which leads to considerable economic damage in the timber industry. Therefore, the occurrence and spread of sooty bark disease raise serious problems. In addition to forestry and economic problems, the conidiospores of C. corticale can also cause health problems in exposed wood workers and they can trigger hypersensitivity pneumonitis (HP). Since the spores, which are deposited over the entire area under the bark of infected trees, can spread during processing, exposed workers must take special precautions to protect themselves against exposure. If an occupational disease is nevertheless suspected following exposure to C. corticale, valid diagnostics are required to confirm possible HP and derive appropriate therapies and exposure reduction or avoidance. Diagnosis of HP is based on several criteria, one of them is the detection of specific IgG in patient's serum against the potentially triggering antigens, in this case C. corticale antigens. To produce a diagnostic tool to measure C. corticale specific IgG, which is not commercially available so far, spores and mycelial material from ITS-sequenced strains of C. corticale was prepared and analyzed. These biochemically characterized extracts of spore and mycelial antigens were biotinylated and coupled to Streptavidin-ImmunoCAPs. To validate these diagnostic test tools the first step is to measure the concentration of C. corticale specific IgG in sera of healthy non-exposed and healthy exposed subjects to establish cut-off values. Suitable participants were recruited and the individual exposure to C. corticale and symptoms experienced during or after working with infected maple trees were recorded using questionnaires. Finally, diagnostic tools for serological testing in suspected cases of HP by C. corticale were created and evaluated. The following article provides recommendations for the treatment and disposal of infected damaged wood and for occupational health protection procedures. Secondly, the diagnosis of HP induced by exposure to C. corticale as an occupational disease is described including the verification of newly developed serological test tools for antigens of C. corticale.

Introduction: Necrotizing fasciitis is a rare but serious complication that can occur in children with chickenpox, even in immunocompetent children. Prompt diagnosis and immediate surgical treatment are mandatory to avoid potentially fatal complications. Cases presentation: The first patient was an 8-year-old female who presented with a 3-day history of varicella infection. Clinical examination revealed general varicella-related exanthema with necrotizing fasciitis in the left groin. In addition to immediate parenteral antibacterial treatment, emergency surgical exploration was done within 3 hours of arrival to the emergency department. Wide surgical debridement was the initial treatment. Primary closure was achieved using a rectus abdominis myocutaneous (RAM) pedicled flap. The postoperative course was uneventful. The second patient was a 6-year-old male with a history of renal disease who presented with a 3-day history of varicella infection to our emergency department. The patient was in a poor general condition and was initially treated with antibiotics for presumed urosepsis. After approximately 2 hours, he developed clear signs of necrotizing fasciitis in the right hemiscrotum. Surgical debridement was immediately performed, but the patient eventually succumbed due to uncontrolled sepsis. Conclusion: Necrotizing fasciitis is a potential complication of patients with chickenpox. Emergent surgical debridement is mandatory.