Clinical Analysis of Metagenomic Next-Generation Sequencing Confirmed Chlamydia psittaci Pneumonia: A Case Series and Literature Review

Figures & data

Table 1 Clinical Characteristics of the Five C. Psittaci Pneumonia Cases

Characteristics	Abnormal Patients/Total Patients, n (%)	Median Value (Range)
Demographics
Age, median (range, years)		51 (36–66)
History of exposure to avian or poultry	3/5 (60)
Underlying disease	3/5 (60)
Clinical manifestations
Fever > 38.5 °C	5/5 (100)	39.1 (38.7–40.5)
Cough, hypodynamia, dyspnea	5/5 (100)
Headache	2/5 (40)
Hypoxemia	5/5 (100)
Invasive ventilator support	2/5 (40)
ECOM support	2/5 (40)
APACHE II		17.6 (8–22)
Days from illness to respiratory failure		4.8 (2–8)
NGS detection sequence number		217 (175–289)
Laboratory testing
WBC (normal 4–10, × 109/L)	4/5 (80)	14.35 (10.4–20.08)
Neutrophil ratio (normal 45–75%)	5/5 (100)	93.03 (80.5–97.7)
CRP (normal 0–8 mg/L)	5/5 (100)	129.83 (16.8–423)
PCT (normal 0–0.05 ng/mL)	5/5 (100)	10.12 (0.058–100)
ESR (normal 0–15mm/h)	5/5 (100)	65.64 (25–100)
CK (normal 30–135 U/L)	5/5 (100)	2261.18 (14–8842.2)
LDH (normal 109–245 U/L)	5/5 (100)	737.96 (252.9–1433.1)
ALT (normal 9–50 U/L)	5/5 (100)	310.17 (65.7–2889.7)
AST (normal 15–40 U/L)	5/5 (100)	1554.11 (40.4–23,553.3)
Hypokalemia (normal 3.5–5.3 mmol/L)	3/5 (80)	3.1 (2.7–3.3)*
Hemoglobin
Treatment
Doxycycline	2/5 (40)
Moxifloxacin	1/5 (20)
Moxifloxacin+Doxycycline	2/5 (40)
The duration from admission to diagnosis (days)		3 (2–4)
Treatment result
Survive	4/5 (80)
Death	1/5 (20)

Note: *The potassium levels just analyzed the values of hypokalemia patients.

Abbreviations: ECOM, extracorporeal membrane oxygenation; APACHE, The Acute Physiology and Chronic Health Evaluation; CK, creatine kinase; CRP, C-reactive protein; CT, computed tomography; LDH, lactate dehydrogenase; PCT, procalcitonin; ALT, alanine transaminase; AST, aspartate aminotransferase; WBC, white blood cell; ESR, erythrocyte sedimentation rate.

Table 2 Laboratory Inspections Parameters of the Five Patients on Admission

Inspection Items	Case 1	Case 2	Case 3	Case 4	Case5	Reference Value
PH	7.504	7.47	7.52	7.4	7.53	7.35–7.45
Oxygen partial pressure (mmHg)	64.6	42	53.1	59	58	80–100
Partial pressure of carbon dioxide (mmHg)	28.8	29	26.7	27	29	35–45
White blood cell count (x 10^9/L)	16.88	8.43	13.56	5.66	2.1	3.5–9.5
Hemoglobin (g/L)	128	127	68	148	72	130–175
Platelets (x 109/L)	183	129	325	83	100	125–350
C reactive protein (mg/L)	423	109.12	434	179.5	191.59	0–8
Procalcitonin (ng/mL)	18.17	8.1	13.89	58.5	2.75	0–0.05
Erythrocyte sedimentation rate (mm/h)	68	100	–	82	32	0–15
Alanine aminotransferase (IU/L)	146.7	91.7	237	33.4	79.2	9–50
Aspartate aminotransferase (IU/L)	139	115.8	587.6	60	246	15–40
Total bilirubin (umol/L)	20.4	8.9	16.3	12.6	5.8	3.4–17.1
Serum creatinine (umol/L)	71.4	79.7	48.6	338	53.5	44–133
Outcome	Survival	Survival	Survival	Survival	Death

Figure 1 Chest computed tomography (CT) scans of a 66-year-old man with C. psittaci pneumonia. Lungs were exuding consolidation foci, bilateral pectoral effusions, consolidation on the 8th day of hospitalization (A). After treatment, on the 18th day of hospitalization (B), the image of four patients improved, and the patients’ lung exudation, consolidation, and bilateral pleural effusion were less than before.

Figure 2 Chest X-ray of a 36-year-old pregnant female patient with C. psittaci pneumonia and died of septic shock, DIC, and multiple organ failure. (A) on the first day of hospitalization, (B) on the third day of hospitalization, (C) on the sixth day of hospitalization, (D) on the seventh day of hospitalization.

Table 3 Summary of Case Series and Case Report of C. psittaci Pneumonia

Author	Reported Time	Number of Reported Cases	Reported Area	Methods	Anti-Infective Drugs	Clinical Outcome	History of Exposure to Avian or Poultry
Gacouin^Citation4	2012	13	France	mNGS	Tetracycline ± Erythromycin/Levofloxacin	11 patients improved, 2 patients died	Yes
Laroucau^Citation33	2013	8	France	PCR	Macrolides + Cephalosporins	Improved	Yes
Chau^Citation34	2015	3	Hong Kong	PCR	Doxycycline	Improved	Yes
Mair-Jenkins^Citation35	2015	4	United Kingdom	Serology and PCR	Not stated	Improved	No history of direct contact, but someone raises pigeons near the office building
Spoorenberg^Citation36	2016	7	Netherlands	PCR, MIF	2 patients used Tetracycline, Macrolide or Quinolone; 1 patients used β-lactam	Improved	6 patients had an exposure history
Cipriano^Citation37	2016	1	Portugal	IIF	Amoxicillin/Clenauic Acid, Azithromycin	Improved	Yes
Qiu^Citation29	2019	1	China	mNGS	Doxycycline + Moxifloxacin	Improved	No
Zhu^Citation38	2019	1	China	mNGS	Moxifloxacin	Improved	Yes
Shi^Citation39	2019	1	China	PM-seq	Piperacillin/tazobactam + Minocycline	Improved	Yes
Liu^Citation28	2019	1	China	Antibody test	Moxifloxacin	Improved	Yes
Gu^Citation13	2019	5	China	mNGS, IIF	1 patient used Minocycline +Erythromycin	Improved	4 patients had an exposure history
					2 patients used Doxycycline+ Moxifloxacin
					2 patients used Moxifloxacin
Chen^Citation14	2020	9	China	mNGS	Minocycline	8 patients improved, 1 patient died	7 patients had an exposure history
He^Citation40	2020	1	China	mNGS	Doxycycline	Improved	Yes
Chen^Citation30	2020	1	China	mNGS	Moxifloxacin +Cefoperazone Sodium Sulbactam/Meropenem	Improved	Not stated
Katsura^Citation41	2020	1	Japan	PCR	Meropenem+Gamma globulin	Died	Yes
Zhang^Citation42	2020	1	China	mNGS	Doxycycline +Moxifloxacin	Improved	Yes
Zhang^Citation43	2020	1	China	mNGS	Doxycycline + ceftazidime/meropenem	Improved	No
Fernández^Citation44	2020	5	Murcia	mNGS	3 patients used Levofloxacin	Improved	Yes
					+ Doxycycline
					2 patients used Cephalosporin
					+ Doxycycline
Luo^Citation45	2020	5	China	mNGS	2 patients used Doxycycline	Improved	Yes
					1 patients used Doxycycline + Meropenem
					1 patients used Doxycycline + Piperacillin/tazobactam
					1 patients used Doxycycline + Levofloxacin

Abbreviations: mNGS, metagenomics next-generation sequencing; PCR, polymerase chain reaction; MIF, micro-Immunofluorescence; IIF, indirect immunofluorescence; PM-seq, pathogenic microorganisms sequencing.

Figure 3 The summary of C. psittaci pneumonia literature review from 2010 to 2020 year.

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