Viral infection cytomegalovirus

Risk factors in the host can give a clue for the causative pathogen e.g. Chronic Obstructive Lung Disease (COPD) - Haemophilus, alcoholism - Klebsiella, HIV - Pneumocystis. The immunocompromised host is also at increased risk for certain fungal (Aspergillus) and viral infections (cytomegalovirus or CMV). Pseudomonas aeruginosa is frequently involved in exacerbations of cystic tibrosis. 

Organism Viral infections Cytomegalovirus Type of Infection Pneumonia hepatitis chorioretinitis involvement of many other organs Drug Treatment Foscarnet or ganciclovir... 

Infections are major causes of morbidity and mortality in the period after transplantation, whichever immunosuppressive regimen is used, in particular bacterial infections and viral infections (cytomegalovirus, Herpes simplex virus, Epstein-Barr virus), but also protozoal and fungal infections (63-65). Based on an analysis of medical and autopsy records, infections were the cause of death in 70% of transplant patients, with bacteria (50%) or fungi (29%) as the most common pathogens (66). 

Cytomegalovirus (CMV) disease The term used when patients who are already infected with CMV present with classic symptoms that resemble a viral infection and may include fever, malaise, arthralgias, and others. 

Individuals with defects in cellular immunity are prone to fungal, protozoal, and viral infections, such as Candida albicans, cytomegalovirus, and Pneumocystis carinii, since cell-mediated immune responses are the primary defenses against these types of infection. Because of the role of cell-mediated immunity in tumor surveillance, these individuals will also demonstrate an increased incidence of malignancy if they survive long enough. 

PFA has recently undergone clinical evaluation in humans for the treatment of recurrent genital herpes, hepatitis B viral infection, and acquired immunodeficiency syndrome (AIDS), as well as cytomegalovirus (CMV) infection of bone marrow and renal transplant patients. 

Nephrotic patients (especially children) are prone to bacterial infections. Before antibiotics and corticosteroids were introduced into the therapy, pneumonia, peritonitis, and sepsis (usually caused by pneumococci) were the most frequent cause of death of nephrotic children with minimal change disease. Infections are more frequent in nephrotic children and after the age of 20 their prevalence markedly decreases because the majority of adults have antibodies against the capsular antigens of pneumococci. Infections remain an important complication of nephrotic syndrome in developing countries. In developed countries, nephrotic patients treated by immunosuppressive agents may frequently suffer from viral infections (mainly herpesvirus infections, e.g., cytomegalovirus and Epstein-Barr virus infections). 

Pujol et al. in chapter eight, reviews the chemistry, origin and antiviral activities of naturally occurring sulfated polysaccharides for the prevention and control of viral infections such as HIV-1 and -2, human cytomegalovirus (HCMV), dengue virus (DENV), respiratory syncytial virus (RSV), and influenza A virus. 

Human cytomegalovirus (HCMV) disease is the most common life-threatening opportunistic viral infection in the inmunocompromised. HCMV protease, a serine protease, plays a critical role in capsid assembly and viral maturation and is an attractive target for antiviral chemotherapy. Slater et al investigated the interaction of various 1,4-naphthoquinones derivatives with HCMV protease. They identified potent irreversible naphthoquinones inhibitors of HCMV protease which covalently modify... 

Severe viral infections/reactivation that have been reported in patients given ritnximab have inclnded fnl-minant hepatitis B (18), parvovims-indnced red cell aplasia (15), and fatal Varicella zoster infection (19). There was a high incidence of reactivation of cytomegalovirus and V. zoster virus when rituximab was combined with high-dose chemotherapy in high-risk patients with non-Hodgkin s lymphoma (20). 

Hypersecretion of gastric acid (e.g., Zollinger-Ellison syndrome) Viral infections (e.g., cytomegalovirus)... 

Lymphocytes comprise 15% to 40% of all WBCs and are of central importance to the immune system. Two functional types of lymphocytes are the T cell, which is involved in cell-mediated immunity, and the B cell, which produces antibodies involved in humoral immunity. Lymphocytosis frequently is associated with acute viral infections such as Epstein-Barr virus infection (mononucleosis) and cytomegalovirus in fection and rarely with unusual bacterial infections (i.e.. Brucella spp. infections). 

Murray HW, Knox DL, Green WR, Susel RM. Cytomegalovirus retinitis in adults a manifestation of disseminated viral infection. Am J Med 1977 63 574. 

Ganciclovir is similar in mode of action. Adverse reactions can be severe so this drug is reserved for serious viral infections such as cytomegalovirus in immunocompromized patients. 

The principal toxicities of mycophenolate are gastrointestinal and hematologic. These include leukopenia, diarrhea, and vomiting. There also is an increased incidence of some infections, especially sepsis associated with cytomegalovirus. Tacrolimus in combination with mycophenolate mofetil has been associated with devastating viral infections including polyoma nephritis. 

A substantial number of phosphonates have been prepared and tested against viral infections, including AIDS. Even relatively simple compounds such as the above-mentioned phosphonoformic acid (19, = 0) and phosphonoacetic acid (19, n= 1) were reported as antivirals and herpes virus inhibitors active against acyclovirresistant herpes and cytomegalovirus retinitis in patients with AIDS . The veterinary use has been mentioned ... 

The first antisense therapeutic agent to reach the market is fomivirsen (ISIS 2922) (19). Fomivirsen is a 21-mer phosphorothioate oligodeoxynucleotide (Fig. 8.5). It inhibits human cytomegalovirus (CMV), a ubiquitous herpesvirus that is the most common cause of viral retinitis in immunocompromised patients, especially those with FIIV infection. Cytomegalovirus infection is characterized by the progressive destruction of retinal cells and, if untreated, leads to retinal detachment and blindness. Even with treatment, some degree of visual loss occurs in nearly all patients with a diagnosis of CMV retinitis. It can affect one or both eyes. 

Beisser PS. The R33 G protein-coupled receptor gene of rat cytomegalovirus plays an essential role in the pathogenesis of viral infection. J Virol 1998 72(3) 2352-63. 

Soderberg-Naucler C, Fish KN, Nelson JA (1997) Reactivation of latent human cytomegalovirus by allogeneic stimulation of blood cells from healthy donors. Cell 91 119 126 Speir E, Shibutani T, Yu ZX, Ferrans V, Epstein SE (1996) Role of reactive oxygen intermediates in cytomegalovirus gene expression and in the response of human Smooth muscle cells to viral infection. Circ Res 79 1143 1152... 

---