Pulmonary abscess caused by Streptococcus pseudopneumoniae in a child: A case report and review of literature

Table 1 Laboratory tests conducted after admission

Laboratory test	Results	Reference value
WBC (L)	10.6 × 109	5.1-14.1 × 109
Neutrophil count (L)	4.88 × 109 (46%)	0.8-5.8 × 109
Lymphocyte count (L)	4.1 × 109 (38.7%)	2.4-8.7 × 109
Monocyte count (L)	1.4 × 109 (12.8%)	0.18-1.13 × 109
Hemoglobin (g/L)	106 g/L	107-141
Platelet count (L)	354 × 109	190-524 × 109
C-reactive protein (mg/L)	65.45	< 10
Interleukin- 6 (pg/mL)	24.82	< 7.0
Procalcitonin (ng/L)	0.85	< 0.05
ESR (mm/h)	65	0-15
Blood coagulation function test	Normal	Normal
Immunoglobulin testing (5 items)	Normal	Normal
Liver function	Normal	Normal
Renal function	Normal	Normal
Myocardial enzyme	Normal	Normal
T-SPOT.TB, PPD, Tuberculosis smear (BALF)	Negative	Negative
Pharynx swab, Blood, BALF culture	Negative	Negative
Serum respiratory pathogen antibody (6 items)1	Negative	Negative
Respiratory tract pathogen PCR (27 items)2	Negative	Negative
Mycoplasma pneumoniae DNA (BALF)	< 1.0 × 104	< 1.0 × 104
mNGS (BALF)	Pathogens: Streptococcus pseudopneumoniae: 36449 sequences. Human herpesvirus 5: 926 sequences. Human parainfluenza virus type 3: 2089 sequences
	Antibiotic resistance genes: No antibiotic resistance genes were detected
	Genes specific to Streptococcus pseudopneumoniae: Pseudo_232, 901, 231, 902, 899, 228, 1764, 641, 1933 (5)
	PLY gene

¹The words in bold are obvious outliers. The six serum respiratory pathogens included Mycoplasma pneumoniae, Chlamydia pneumoniae, Legionella pneumophila, enterovirus, respiratory syncytial virus and adenovirus.

²The 27 respiratory tract pathogens included Group B Streptococcus, H1N1 influenza A virus, H3N2 influenza A virus, H3 influenza A virus, H5 influenza A virus, H7 influenza A virus, pertussis bacterium, rhinovirus, Boca virus, Enterovirus, Streptococcus pneumoniae, Chlamydia pneumoniae, Mycoplasma pneumoniae, parainfluenza virus type 1, parainfluenza virus type 2, parainfluenza disease type 3, parainfluenza virus type 4, coronavirus, respiratory syncytial virus, Streptococcus pyogenes, influenza A virus, Moraxella catarrata, Haemophilus influenzae, human metapneumovirus, Legionella pneumophila, adenovirus, and influenza B virus.

WBC: White blood cell; ESR: Erythrocyte sedimentation rate; BALF: Bronchoalveolar lavage fluid; T-SPOT.TB: Tuberculosis-specific enzyme-linked immunospot assay; PPD: Purified protein derivative; PCR: Polymerase chain reaction.

Table 2 Timeline of patient’ s course of illness

Date	Symptoms onset	Imaging examination	Treatments administered	Follow-up outcomes
August 30, 2023	Persistent cough for seven days and fever for five days	None	Ceftazidime was given for anti-infective treatment	Temperature returned to normal
September 2, 2023	Temperature was normal, but cough was still serious	Pulmonary CT	Continue anti-infective treatment	Inflammation of the posterior upper lobe of the right lung with abscess formation
September 4, 2023	The frequency of coughing slightly decreased	None	Bronchoalveolar lavage	The frequency of coughing decreased.
September 8, 2023	The frequency of coughing obviously disappeared	Pulmonary CT	Continue anti-infective treatment
September 14, 2023	None	None	Cefdinil was given for anti-infective treatment	Hospital discharge
October 9, 2023	None	Pulmonary CT	None	The abscess was resorbed and the patient’s outcome was good

CT: Computed tomography.