Severe acute respiratory syndrome treatment

A new coronavirus was quickly identified after the outbreak of an atypical pneumonia in southern China early in 2003. The new virus eventually caused 8,000 infections with approximately 800 deaths in 29 countries. The condition was named Severe Acute Respiratory Syndrome, SARS, and the causative coronavirus named SARS-CoV. The zoonotic nature of the infection came with the identification of a similar virus in bats (Poon et al. 2005), although it is possible that the bat virus passed through other animal hosts and recombined with other SARS-like coron-aviruses prior to infecting humans (Hon et al. 2008). SARS-CoV is not currently circulating in the human population however, the mysterious appearance and rapid spread of this virus emphasized how vulnerable the human population is to such respiratory infections. This has spurred interest in the development of antivirals that could be used either in treatment or as prophylaxis to complement public health measures in curbing future outbreaks. 

A system that determines the specific threat agent such that complete response actions, including medical treatment, are possible. (A caveat is that for unknown threat agents that have emerged or are engineered, identification can be delayed, such as for severe acute respiratory syndrome.) These can be exclusively technology based or human based or both. 

The first effective and safe treatments for Alzheimer s, Parkinson s, chronic graft rejection, permanent graft acceptance, obesity, chronic obstructive pulmonary disease (COPD), adult respiratory distress syndrome (ARDS), sepsis, and vaccines [common cold, respiratory syncytial virus (RSV), severe acute respiratory syndrome (SARS), AIDS, malaria. Avian Influenza, radiation, contraception, emerging new infections] will be multibillion-dollar products [15,16]. 

Yamai M, Tsumura K, Kimura M et al (2003) Antiviral activity of a hot water extract of black soybean against a human respiratory iUness virus. Biosci Biotechnol Biochem 67 1071-1079 Yang CM, Cheng HY, Lin TC (2007) Hippomanin A from acetone extract of Phyllanthus urinaria inhibited HSV-2 but not HSV-1 infection in vitro. Phytother Res 21 1182-1186 Yi L, Li Z, Yuan K, Qu X et al (2004) Small molecules blocking the entry of severe acute respiratory syndrome coronavirus into host cells. J Virol 78 11334-11339 Yura Y, Yoshida H, Sato M (1993) Inhibition of herpes simplex virus replication by genistein, an inhibitor of protein-tyrosine kinase. Arch Virol 132 451 61 Zakay-Rones Z, Thom E, Wollan T (2004) Randomized study of the efficacy and safety of oral elderberry extract in the treatment of influenza A and B virus infections. J Int Med Res 32 132-140... 

A 32-year-old woman with acute promyelocytic leukemia developed severe retinoic acid syndrome after 3 days, with respiratory failure, fever, and bilateral lung infiltrates. Withdrawal of tretinoin and treatment with dexamethasone and antibiotics rapidly ameliorated the syndrome, and on day 10 tretinoin was restarted. However, routine echocardiography showed a 3 cm pedunculated mass in the right ventricle. There was consistent and stable reduction of the mass after 1 year of oral anticoagulant therapy. 

Multiple studies have addressed the role of thyroid supplementation in critically ill patients with cardiac disease, sepsis, pulmonary disease (e.g., acute respiratory distress syndrome), or severe infection, or with burn and trauma patients. In spite of a very large number of published studies, it is very difficult to form clear recommendations for treatment with thyroid hormone in the intensive care unit. 

Indications for renal replacement therapy in the acute setting and for other disease processes are different from those for ESRD. A common mode of ESRD therapy in the outpatient setting is intermittent hemodialysis (IHD) where a patient receives intense treatment over the course of a few hours several times a week. Acute renal failure in the inpatient setting is often treated with continuous renal replacement therapy (CRRT), which is applied for the entire duration of the patient s clinical need and relies upon hemofiltration to a higher degree than IHD (Meyer, 2000). Other nonrenal indications for CRRT are based on the theoretical removal of inflammatory mediators or toxins and elimination of excess fluid (Schetz, 1999). These illnesses include sepsis and systemic inflammatory response syndrome, acute respiratory distress syndrome, congestive heart failure with volume overload, tumor lysis syndrome, crush injury, and genetic metabolic disturbances (Schetz, 1999). 

Gaseous nitric oxide is a short-lived molecule that has been used in the treatment of patients with primary pulmonary hypertension and is used in subgroups of severely ill and hypoxic children with persistent pulmonary hypertension of the newborn, in preterm infants of less than 34 weeks gestation, and in adults with acute lung injury and adult respiratory distress syndrome. There are some reports of its use for intestinal ischemia, reperfusion injury, thrombotic disorders, and sickle cell crises. 

Figure 4 Possible pathophysiologic events involving innate and adaptive immunity, leading to BOS/OB. Repeat milder stimuli to the respiratory epithelium (such as for instance GER, colonization, etc.) may lead to stimulation of innate immunity ending up in neutrophilic airway inflammation, which may be reversible upon treatment with azithromycin. However, if left untreated, chronic neutrophilic inflammation and increased oxidative stress may further stimulate fibroblast activation, epithelial to mesenchymal transition, with migration of (myo)fibroblasts, leading to fibrosis of the airway wall and fibrotic plugs in the airways, typically for OB. A more severe epithelial injury (as for instance in acute rejection and CMV infection) may directiy lead to fibroblast activation and OB in a short time period, without any neutrophils being present in the airways. Abbreviations BOS, bronchiolitis obliterans syndrome OB, obliterative bronchiolitis GER, gastroesophageal reflux CMV, c) tomegalovirus.

Respiratory effects occur in a dose-dependent manner from the nasal mucosa to the terminal bronchioles (WHO, 1970 Balali-Mood et al., 1986). Acute pulmonary effects commence with a tracheobronchitis, followed by bronchopneumonia, adult respiratory distress syndrome, and even pulmonary emboli in severely intoxicated patients, which may lead to death, mostly during the second week after SM exposure. Chest X-ray (CXR) of the Iranian SM-intoxicated patients revealed fewer abnormalities than the clinical manifestations. However, the severely intoxicated patients showed abnormal CXR results. CXRs of an Iranian patient with bronchopneumonia caused by acute SM poisoning before and after treatment in 1985 are shown in Figure 5.2. 

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