Pneumonia, atypical J18.9

In 1938, Hobart Reimann was the first to describe a pneumonia in which the typical signs of (typical) lobar pneumonia were missing and called this " atypical pneumonia".

Atypical pneumonia is an acute or chronic inflammation of the interstitium of the lung.

Chlamydia, mycoplasma, Legionella, Pneumocystis jiroveci, viruses

• slow start
• General condition usually only slightly to moderately impaired
• often only moderate fever
• barren cough
• Shortness of breath (approx. 30%)
• Cephalgias, myalgias, gastrointestinal symptoms
• rarely tachypnea and/or tachycardia
• Leukocytes in the normal range (!) with relative lymphocytosis
• rarely positive blood cultures
• considerable discrepancy between the low auscultation findings and the X-ray image

Interstitial proliferation of drawings; shadows distributed over all lung fields, blurred and accentuated in the core.

- Sputum sample for germ determination for atypical pathogens (if no sputum is available, it should be obtained bronchoscopically)

- Urine antigen test for Legionella (only detects serogroup I, therefore additional antibody serology)

- Pathogen detection (culture, PCR)

- serological antibody detection for atypical pathogens

• Clinic: see above
• detailed anamnesis: question about timely hotel accommodation, stay near water facilities, contact with domestic birds or poultry
• Auscultation: Rarely can sound rattle noises be heard
• Laboratory: - Sputum sample for the determination of germs for atypical pathogens (if no sputum is available, it should be obtained bronchoscopically)
• Urine antigen test for Legionella (only detects serogroup I, therefore additional antibody serology)
• Pathogen detection (culture, PCR)
• serological antibody detection for atypical pathogens

Pneumonia of other genesis

Depending on the pathogen can be effective:

• Tetracyclines (2x100mg/day)
• Macrolides (Clarithromycin 2x500mg/day; Azithromycin:1x500mg/day; Roxithromycin: 1x300mg/day)

• Ketolide

• Fluoroquinolones (moxifloxacin: 400mg/day; lefloxacin: 500mg/day)

In the case of a serious clinical picture and the justified suspicion of atypical pathogens, dual therapy should be started immediately, as the diagnosis is sometimes time-consuming. After receipt of the pathogen proof, modification of the antibiosis.

The highest mortality rate of atypical pneumonia is found in Legionella-induced disease. It is - even with adequate therapy - about 10% and rises to > 50% in immunocompromised or pre-existing cardiovascular diseases.

The mortality rate of the other pathogens is significantly lower.

There is a nationwide obligation to report by name in accordance with IfSG § 7 in the case of direct or indirect evidence of legionella, as far as this indicates an acute infection.

In addition, there is a special status of the state of Saxony: Mention by name of an acute infection with Mycoplasma species.

1. Harrison et al (2015) Internal Medicine: 804-811
2. Herold et al (2017) Internal Medicine: 375-384
3. Hof H (2015) More attention for Pneumocystis Pneumonia - A differential diagnosis in risk patients. Clinician 44: 56-57
4. Matthys / Seeger (2008) Clinical pneumology: 316-322
5. Osterlee U (2016) Treat twice if atypical pneumonia is suspected. Pneumonews 8: 29
6. RKI (2018) Epidemiological Bulletin 49/1999
7. SächsGVBl. (2002) No. 9/187 Fsn-Nr.: 250-6/2 §3
8. Suttorp et al (2004) Infectious diseases: 113
9. Wehling M (2011) Clinical Pharmacology: 526-543