Contents
Opportunistic infection
Patients with Systemic connective tissue diseases: or vasculitis diseases often gets a little weakened immune system when treated with immunosuppressive drugs. Thus, usually harmless microbes (bacteria, viruses, fungi, parasites) can cause unusual infections (opportunistic infection). Also other infections (latent virus, Tuberculosis and other infections) can flare up and get a more serious course than expected. Someone gets Multiresistant bacteria can cause infections. For the prognosis, it is nevertheless important to recognize the symptoms and make the right examinations as early as possible.
Suppressive treatment
Examples of immunosuppressive anti-rheumatological treatment that increase the risk of infections:
- High doses of cortisone (SoluMedrol, Prednisone)
- Sendoxan
- Biological drugs
- JAK inhibitors
- Neutropenia (Low number of Neutrophilic white blood cells)
- For example, when other parts of the immune system are impaired by kidney inflammation (Glomerulonephritis)
- By HIV infection when CD4 T cell numbers are low (
- In case of congenital immune deficiency or other causes low immunoglobulins
- Other reduced functions of the immune system
Preventive measures
Before starting immunosuppressive treatment like MabThera / Rixathon (Rituximab), RoActemra (Tocilizumab) and some others biological drugs it is common to rule out signs of blood infections by blood tests:
- Hepatitis B og Hepatitis C
- HIV (AIDS virus)
- Tuberkulosis (Tbc) (Tbc) (active or latent) in blood sample (Interferon Gamma Release Assay, IGRA test)
Vaccination against pneumococcal infection (Vaccine against pneumonia) and flu are often a good preventive measure
Detection of opportunistic infection
- CT of lungs
- CT abdomen (Differential diagnosis lymphoma fever)
- MR with contrast of the brain:
- Spinal fluid examination
- Rectal brush (vancomycin resistant enterococci, VRE)
- Mushrooms or mycobacteria by culture (special staining), histology, biopsy, or PCR
- Antibody occur late in the course (especially in immunosuppressed):
- PCR, ELISA, direct immunofluorescence provides quick response and is requested whenever possible
- High procalcitonin indicates bacterial infection
- Parasites can be detected by wound biopsy (leishmaniasis) blood (Chagas disease), stool (cryptosporoidose)
A study from the USA (reference: Baddley JW, 2014) confirmed that patients treated with TNF inhibitors were more prone to Opportunistic infections. The following non-viral infections were recorded:
- Pneumocystis (PCP) (20%)
- (Classified as fungal infection)
- Nocardiosis / actinomycosis (12,15%)
- Tuberkulosis (Tbc)
- (12,5%)
- Histoplasmosis (11,3%)
- Unlikely in Europe
- Non-tuberculous mycobacteria (11,3%)
- Salmonellosis (10%)
- Listeriosis (5%)
- Legionellosis (5%)
- Cryptococcal infection (3,8%)
- Endemic fungal infection (1,3%)
- Toxoplasmosis (1,3%)
- Coccidioidomycosis (1,3%)
- Blastomycosis (1,3%)
- Unlikely in Europe
- Aspergillosis (1,3%)
Some other relevant infections with links to more information:
- Adenovirus
- BK virus
- Candidiasis
- Chikungunya
- Clostridium difficile
- Cryptococcus infection
- Cryptosporidiosis parasite
- Cytomegalivirus (CMV)
- Epstein Barr virus (EB)
- Can trigger MAS / HLH at disposal
- Mononucleosis
- Giardiasis parasite
- Hepatitis B
- Hepatitis C
- Herpes simplex
- Herpes Zoster («shingles)
- HIV
- JC virus (JCV) and PML infection (progressive multifocal leukoencephalopathy)
- MRSA (Methilicin resistant staphylococcus aureus)
- Mycoplasma
- Parvovirus B 19
- PML (JC Virus) Progressive Multifocal Leukoencephalopathy
- Pseudomonas
- Q fever
- Trichinosis
- Ureaplasma urealyticum
- Norwegian description of a case (Kvalvik SA, 2020)
- Vankomycin resistant enterococci (VRE)
