The aetiology, prevalence and morbidity of outbreaks of photosensitisation in livestock: A review.

BACKGROUND: Photosensitisation is a clinical condition occurring in both humans and animals that causes significant injury to affected individuals. In livestock, outbreaks of photosensitisation caused by ingestion of toxic plants are relatively common and can be associated with significant economic loss. OBJECTIVES: The agents that are most commonly implicated in outbreaks of photosensitisation have not been formally investigated on a global scale. To address this question, a systematic review of the literature was undertaken to determine the most common causative agents implicated in outbreaks of photosensitisation in livestock in Australia and globally, as well as the prevalence and morbidity of such outbreaks. METHODS: A systematic database search was conducted to identify peer-reviewed case reports of photosensitisation in livestock published worldwide between 1900 and April 2018. Only case reports with a full abstract in English were included. Non peer-reviewed reports from Australia were also investigated. Case reports were then sorted by plant and animal species, type of photosensitisation by diagnosis, location, morbidity and mortality rate and tabulated for further analysis. RESULTS: One hundred and sixty-six reports qualified for inclusion in this study. Outbreaks were reported in 20 countries. Australia (20), Brazil (20) and the United States (11) showed the highest number of peer-reviewed photosensitisation case reports from this analysis. Hepatogenous (Type III) photosensitisation was the most frequently reported diagnosis (68.5%) and resulted in higher morbidity. Panicum spp., Brachiaria spp. and Tribulus terrestris were identified as the most common causes of hepatogenous photosensitisation globally. CONCLUSIONS: Hepatogenous photosensitisation in livestock represents a significant risk to livestock production, particularly in Australia, Brazil, and the United States. Management of toxic pastures and common pasture weeds may reduce the economic impact of photosensitisation both at a national and global level.

Acute photosensitisation and mortality in a herd of dairy cattle in Tasmania.

CASE HISTORY: A herd of Holstein, Jersey, or Holstein-Jersey cross lactating cattle of mixed ages presented with a sudden drop in milk yield in 94/678 cows on 3 October 2014 (Day 0). The herd was located in Gretna in the Derwent Valley (Tasmania, Australia) and had been grazing dryland pasture. CLINICAL FINDINGS: On Day 0 the cows variably showed recumbency, peracute photosensitisation, inflamed coronary bands, conjunctival erythema, periauricular oedema, distress indicated by kicking at the flank, bruxism, discomfort, weight shifting, vocalisation indicating pain and depression. Blood samples collected on Day 4 from five clinically affected cows showed high activities of aspartate aminotransferase, glutamate dehydrogenase and gamma-glutamyl transferase. Morbidity, based on the number of treated cases within 72 hours of clinical onset, was estimated at 165/678 cows (24.3%). Mortality over the first 30 days was 19/678 cows (2.8%). PATHOLOGICAL FINDINGS: Necropsies of two cows on Day 4 showed marked distension of the gall bladder and extensive icterus. Necropsies of another two cows on Day 5 showed enlarged livers with severe damage and oedema of the distal abomasum. Severe ulcerative abomasal gastritis was present in both cows. Hepatic histopathology was consistent with chronic cholangiohepatitis. MYCOTOXICOLOGY: Fifty-five different mycotoxins were detected from a barley grass (Hordeum murinum) sample from the presumably contaminated pasture. Concentrations of B-trichothecenes, fumonisins, and zearalenone metabolites from this sample were remarkably high. The leaf smut, Jamesdicksonia dactylidis, that has not been previously reported in Tasmania, was identified from the sample of barley grass, but it is not known whether the smut can produce toxins. DIAGNOSIS: Probably an undescribed peracute mycotoxicosis associated with the ingestion of contaminated dryland pasture. CLINICAL RELEVANCE: A definitive diagnosis could not be reached in this case of acute photosensitisation and mortality in dairy cattle grazing possibly contaminated dryland pasture. The findings differed from both facial eczema and acute bovine liver disease, suggesting an undescribed mycotoxicosis.

[Graft-versus-host disease (GvHD) - an update. Part 2: prognosis and therapy of GvHD]. / Graft-versus-Host-Disease (GvHD) - ein Update. Teil 2: Prognose und Therapie der GvHD.

Graft-versus-host disease (GvHD) remains one of the major complications after allogeneic stem cell transplantation (SCT) and is responsible for morbidity, mortality and decrease in quality of life of patients after SCT. The most important preventive approach is the selection of a donor with best possible HLA compatibility between donor and recipient. Basic prophylaxis of acute GvHD begins already prior to transplantation and usually consists of cyclosporine with or without methotrexate. In the past few years, many new therapies have been introduced for the treatment of acute and chronic GvHD. Extracorporeal photopheresis (ECP), for example, represents a promising treatment option for acute and chronic GvHD with very few side effects. For chronic GvHD mTOR inhibitors (sirolimus, everolimus) may replace calcineurin-inhibitors with the advantage of not inducing malignant skin tumors. Guidelines are available ort he management of acute and chronic GvHD. While pathophysiology, classification and skin manifestations of GvHD have been already presented in the first part of this article, this second part covers the prognosis, prevention and treatment of GvHD.

Kindler syndrome: a study of five Egyptian cases with evaluation of severity.

BACKGROUND: Kindler syndrome (KS) is a rare genodermatosis characterized by four major features (acral blisters, photosensitivity, poikiloderma, and cutaneous atrophy) and many associated findings. The diagnosis of KS includes clinical features, ultrastructural findings, and, recently, immunostaining and genetic studies. Varying degrees of severity of the syndrome have been described. METHODS: Five patients with clinical features consistent with KS were included in this study. All patients were subjected to histopathologic and ultrastructural studies. RESULTS: Cases 1 and 2 presented with severe major features, severe mucosal involvement, and many other associated findings. Case 3 presented with severe major features, but mild and limited mucosal involvement and other associated findings. Cases 4 and 5 showed mild major features and few other findings. Histopathology revealed nonspecific poikiloderma. Marked thickening of the lamina densa and splitting of the lamina lucida were the main ultrastructural findings. CONCLUSION: KS may be classified into mild, moderate, and severe according to the severity of the major features and mucosal involvement. Because histopathologic and ultrastructural findings are not pathognomonic, clinical features remain the mainstay for the diagnosis of KS, and the need for immunostaining with kindlin antibody and genetic studies may be restricted to early cases with incomplete features.

Recovery of hepatic function and latent mortalities in sheep exposed to the blue-green alga Microcystis aeruginosa.

Seventeen sheep died, and many others showed signs of hepatogenous photosensitivity after being exposed to Microcystis aeruginosa at Lake Mokoan, Victoria, Australia. Two groups of sheep were observed, and their hepatic recovery was monitored by means of serum biochemical tests during the subsequent six months. During the first three weeks, their serum gamma-glutamyl transferase activity and bilirubin concentration declined rapidly to normal levels, and the signs of hepatogenous photosensitivity disappeared. Serum bile acid concentrations were above normal for almost three months. Thirty-four per cent of the sheep died during the observation period, and the serum biochemical tests provided no clear indication of the cause of these delayed mortalities. This study suggests that sublethal exposure to microcystins may cause prolonged morbidity and delayed mortality.

The photosensitivity dermatitis and actinic reticuloid syndrome: no association with lymphoreticular malignancy.

In the management of photosensitivity dermatitis/actinic reticuloid syndrome (PD/AR) (syn. chronic actinic dermatitis), a chronic and often severe photodermatosis, there has been concern that patients may be predisposed to the development of lymphoreticular malignancy. A follow-up study of 231 patients with PD/AR who had been investigated at the Photobiology Unit, Ninewells Hospital, Dundee, between 1971 and 1991, was undertaken to determine (i) the incidence and type of malignancies (ii) the causes of any deaths. This information was obtained from three sources: (a) National Cancer Registry data, (b) death certificates, (c) when possible or practical, by casenote review. Thirty-eight malignancies had occurred (in 37 of the 231 patients). Although six of the 38 malignancies were lymphoma registrations, it emerged from a review of casenotes, pathology reports and death certificates that five of the six were incorrect: two were labelled 'mycosis fungoides' prior to diagnosis of PD/AR; a case of dermatopathic lymphadenopathy was initially reported as Hodgkin's disease; clerical errors had occurred in two cases. The remaining case was a true B-cell lymphoma. The occurrence of one lymphoreticular malignancy is not significantly different from the number expected in a normal population (0.96), when applying 5-year age-, sex-, and site-specific incidence rates to the cumulative patient years of risk [standardized incidence ratio 1.04 (95% CI 0.03-5.79)]. There was also no significant increase in the risk of non-lymphoma malignancies in the PD/AR subjects. Since diagnosis, 83 patients have died, the majority from cardiorespiratory or cerebrovascular diseases, or the reported malignancies, a pattern expected in an elderly population.(ABSTRACT TRUNCATED AT 250 WORDS)

[Pathogenesis of porphyrin-sensitized lethal and sub-lethal photo-injury]. / Patogenez sensibilizirovannogo porfirinami letal'nogo i subletal'nogo fotopovrezhdeniia.

By means of morphological methods the mechanisms of thanatogenesis were studied in 57 white mice after the hematoporphyrin derivative administration and xenon lamp radiation imitating the sun spectrum. In dependence of integrative doses of sensitized photoradiation and individual resistance of the organism there was observed immediate (hours), retained (days) and remote (weeks) death of animals. In the first two groups death came as a result of photocoagulation of plasma proteins and toxemic shock with liver, lung and brain injury, and in the third group--as a result of suppurative resorptive intoxication against the background of ulcerous skin necrosis.

Experimental photosensitization and toxicity in sheep produced by Tetradymia glabrata.

Factors affecting the phototoxic response of sheep to Tetradymia glabrata were investigated. Photosensitization, which occurs regularly in the field situation, was unpredictable and difficult to produce experimentally. In attempting to understand this unpredictability we concluded that the plant does not lose its toxicity after field collection either through volatility of the toxin, plant enzymatic degradation of the toxin or dehydration. The chlorophyll source, from which the suspected phototoxic agent phylloerythrin is derived, did not appear to be important. The single case of photosensitization produced gave no clues as to why it occurred. Some predisposing factors important to the production of tetradymia related photosensitization in sheep are unknown. In disagreement with previous reports the hepatotoxic response of sheep to Tetradymia glabrata was extremely variable. Also plants in comparable stages of growth, but from different locations, varied in their toxicity to sheep. Young budding plants are most toxic, however, toxicity of the plant remains through maturity.