In the name of God
Principles of post Tx infections 1: Potential etiologies of infection in these patients are diverse, including common and uncommon opportunistic infections. Infection processes can progress rapidly and may constitute medical emergencies. Infections are often advanced (ie, disseminated) at the time of clinical presentation because of impaired immunity. It is due to diminished symptoms and muted clinical and radiologic findings. Serologic testing is not generally useful for the diagnosis of acute infection in the immunocompromised host since seroconversion is often delayed. Altered anatomy following transplant surgery may change the physical signs of infection.
Principles of post Tx infections 2: Tissue biopsies i with histopathology th and microbiology are often needed to make a specific microbiologic diagnosis in transplant recipients. The choice of antimicrobial regimens is often more complex than in other patients due to the urgency of therapy and the frequency of drug toxicities iti and drug interactions. ti Antimicrobial resistance is increased in immunocompromised hosts and should be considered in the choice of antimicrobial regimens. Surgical intervention is often necessary to cure localized infections i (ie, debridement); antimicrobial i agents alone are frequently inadequate. Drug levels provide only crude means of monitoring immunosuppressive regimens and patients are often more or less immunosuppressed than anticipated.
Epidemiology of Post TX infections Community acquired pathogens respiratory viruses (influenza respiratory viruses (influenza, parainfluenza, respiratory syncytial [RSV] virus, adenovirus, and human metapneumovirus). In addition, common bacterial pathogens may include: Streptococcus pneumoniae, Mycoplasma, Legionella, Listeria monocytogenes, and Salmonella. Vaccinations for pneumococcus and influenza virus are useful but may have reduced efficacy in immunocompromised individuals. (See "Immunizations in solid organ transplant candidates and recipients".) In the appropriate geographic regions, endemic fungi (Histoplasma capsulatum, Coccidioides spp, Blastomyces dermatitidis, Cryptococcus gattii), and common environmental pathogens (eg, Cryptococcus neoformans, Aspergillus spp, Cryptosporidia spp) will be observed. Reactivation of infections Reactivated infection may be derived from the organ donor or the recipient. Common viral infections that frequently reactivate following transplantation include herpes simplex virus (HSV), CMV, varicella zoster virus, (HBV), and (HCV), papillomavirus, and BK polyomavirus. Nosocomial infections Pathogens include: Legionella L i spp and other gram negative bacilli such as Pseudomonas aeruginosa. Gram positive organisms, particularly antimicrobial resistant species such as vancomycin resistant enterococci (VRE) and (MRSA)
Infectious considerations in the evaluation of potential organ donors and recipients Viral infection Acute viremia (eg, Herpes simplex virus, adenovirus, lymphocytic choriomeningitis virus, hepatitis A, West Nile virus),active shingles (varicella zoster infection) or herpes virus pneumonitis,acute Epstein Barr virus (mononucleosis),hiv infection (serologic or molecular evidence),active hepatitis B or hepatitis C, Human T cell lymphotropic virus I/ II II (no longer an absolute contraindication in non endemic regions),sars Bacterial infection Ati Active tuberculosis, Untreated t pneumonia, Untreated t syphilis, Multisystem t organ failure due to overwhelming sepsis or gangrenous bowel, Active toxoplasmosis (prophylaxis effective), Fungal and parasite infection Parasitic infection, Active Trypanosoma cruzi, Leishmaniasis, candidiasis, Nocardia, Histoplasmosis, Strongyloidiasis.
Common viral infections in solid organ transplant recipients Herpes group Herpes simplex Varicella zoster Epstein Barr virus Cytomegalovirus HHV6 HHV7 HV8/KSHVHV8/KSHV Donor derived West Nile virus Rabies LCMV Hepatitis B Hepatitis C Papillomavirus Polyomavirus BK/JC Respiratory viruses Adenovirus RSV Influenza Parainfluenza Metapneumovirus SARS coronavirus Parvovirus B19 HIV