Int J Clin Pediatr

International Journal of Clinical Pediatrics, ISSN 1927-1255 print, 1927-1263 online, Open Access

Article copyright, the authors; Journal compilation copyright, Int J Clin Pediatr and Elmer Press Inc

Journal website https://www.theijcp.org

Case Report

Volume 11, Number 1, March 2022, pages 20-26

The Management of Influenza Virus-Induced Plastic Bronchitis in Pediatric Patients: A Case Report and Literature Review

Figure 1. Chest radiography and computed tomography on admission day. (a) Chest radiography on admission revealed the low permeability in the left lung field. (b, c) Chest computed tomography (axial and coronal) revealed the decreasing permeability in the left lung field.

Figure 2. Clinical course after admission. This figure showed time course of applied medicine and chest radiography. SBT/AMPC: sulbactam/ampicillin; AMPC/CVA: amoxicillin-clavulanate.

Figure 3. Chest computed tomography on day 4 following admission (axial and coronal) revealing the total atelectasis in the left lung field and a mucous plug in the left bronchus.

Figure 4. (a-f) Bronchoscopic visualization of secretions in the bronchus with patent left lobe orifice. The author (presenter, otolaryngologist) performed flexible bronchoscopy, which revealed a whitish rubbery material occluding the left lower lobe bronchus, and plastic casts were removed. The casts fragmented were removed by extraction via suctioning during fiberoptic bronchoscopy.

Figure 6. Chest radiography after bronchoscopic suctioning. (a) Finding immediately after bronchoscopic suctioning. After bronchoscopic removal of casts, the atelectasis finding in the left upper lung on chest radiography was improved. (b) Chest radiography revealed a marked improvement in the left lung.

Figure 7. (a, b) Sputum cytopathology (hematoxylin and eosin stain, × 40). Numerous eosinophils were found; however, an evident malignant finding was not found. Eosinophils were considered the inflammatory cells. Charcot-Leyden crystals were not observed.

**Table 1.** Laboratory Data on Admission
^aThese are results of October 3 (hospital day 3). WBC: white blood cell; RBC: red blood cell; Hb: hemoglobin; Ht: hematocrit; Plt: platelet; UN: urea nitrogen; Cr: creatinine; TP: total protein; Alb: albumin; TB: total bilirubin; ALT: alanine aminotransferase; AST: aspartate aminotransferase; Ig: immunoglobulin; CRP: C-reactive protein; RSV: respiratory syncytial virus; Flu: influenza virus; IFN: interferon; MG: microglobulin; NAG: N-acetyl-β-D-glucosaminidase.
WBC	8.2 × 10³/µL
Neutrophils	79.9%
Eosinophils	1.5%
Basophils	1.2%
Lymphocytes	11.0%
RBC	491 × 10⁴/µL
Hb	13.3 g/dL
Ht	40.0%
Plt	25.8 × 10⁴/µL
Na	139 mmol/L
K	4.3 mmol/L
Cl	105 mmol/L
UN	8.0 mg/dL
Cr	0.23 mg/dL
TP	7.2 g/dL
Alb	4.7 g/dL
TB	0.5 mg/dL
AST	23 IU/L
ALT	11 IU/L
IgG	985 mg/dL
IgA	52 mg/dL
IgM	175 mg/dL
CRP	0.10 mg/dL
Non-specific IgE	209 IU/dL
Ferritin	30 ng/dL
RSV	(-)
Flu (A/B)	(-/-)
Mycoplasma	(-)
Cryptococcus	(-)
Blood culture	Negative
Tuberculosis specific IFN-γ	(-)
Urinalysis
Protein	(-)
Blood	(-)
Sugar	(-)
β₂-MG^a	260 µg/L
NAG^a	46 IU/L

Table 1. Laboratory Data on Admission

^aThese are results of October 3 (hospital day 3). WBC: white blood cell; RBC: red blood cell; Hb: hemoglobin; Ht: hematocrit; Plt: platelet; UN: urea nitrogen; Cr: creatinine; TP: total protein; Alb: albumin; TB: total bilirubin; ALT: alanine aminotransferase; AST: aspartate aminotransferase; Ig: immunoglobulin; CRP: C-reactive protein; RSV: respiratory syncytial virus; Flu: influenza virus; IFN: interferon; MG: microglobulin; NAG: N-acetyl-β-D-glucosaminidase.

WBC

8.2 × 10³/µL

Neutrophils

79.9%

Eosinophils

1.5%

Basophils

1.2%

Lymphocytes

11.0%

RBC

491 × 10⁴/µL

13.3 g/dL

40.0%

Plt

25.8 × 10⁴/µL

139 mmol/L

4.3 mmol/L

105 mmol/L

8.0 mg/dL

0.23 mg/dL

7.2 g/dL

Alb

4.7 g/dL

0.5 mg/dL

AST

23 IU/L

ALT

11 IU/L

IgG

985 mg/dL

IgA

52 mg/dL

IgM

175 mg/dL

CRP

0.10 mg/dL

Non-specific IgE

209 IU/dL

Ferritin

30 ng/dL

RSV

(-)

Flu (A/B)

(-/-)

Mycoplasma

(-)

Cryptococcus

(-)

Blood culture

Negative

Tuberculosis specific IFN-γ

(-)

Urinalysis

Protein

(-)

Blood

(-)

Sugar

(-)

β₂-MG^a

260 µg/L

NAG^a

46 IU/L

**Table 2.** A Total 35 Cases of Pediatric Patients With Influenza Virus-Induced Plastic Bronchitis in Previous English Reports
	Influenza type A	Influenza type B
CT: computed tomography.
Case	N = 28	N = 7
Sex (boy/girl)	25:3	6:1
Age	1 year and 10 months to 11 years	5 years to 8 years
Average age	4.4 years	6.9 years
Median age	4 years	6 years
National	Japanese: 10	Japanese: 4
	Korean: 1	American: 3
	Chinese 17
Underlying disease (allergy)	11/28	3/7
Affected side on chest X-ray or CT
Right	7/28	4/7
Left	9/28	3/7
Bilateral	6/28	-
Unknown	6/28	-
Therapy
Antiviral drug	21/28	6/7
Steroid	19/28	5/7
Antibacterial drug	8/28	4/7
Bronchoscopic removal	28/28	7/7
Mechanical ventilation	25/28	6/7
Outcome	26/28 improve including: 2/28 recurrence (the second attack was infected with influenza type B) improve, 2/28 death	7/7 improve including: 1/7 recurrence (the second attack was infected with influenza type A) improve

Table 2. A Total 35 Cases of Pediatric Patients With Influenza Virus-Induced Plastic Bronchitis in Previous English Reports

Influenza type A

Influenza type B

CT: computed tomography.

Case

N = 28

N = 7

Sex (boy/girl)

25:3

6:1

Age

1 year and 10 months to 11 years

5 years to 8 years

Average age

4.4 years

6.9 years

Median age

4 years

6 years

National

Japanese: 10

Japanese: 4

Korean: 1

American: 3

Chinese 17

Underlying disease (allergy)

11/28

3/7

Affected side on chest X-ray or CT

Right

7/28

4/7

Left

9/28

3/7

Bilateral

6/28

Unknown

6/28

Therapy

Antiviral drug

21/28

6/7

Steroid

19/28

5/7

Antibacterial drug

8/28

4/7

Bronchoscopic removal

28/28

7/7

Mechanical ventilation

25/28

6/7

Outcome

26/28 improve including: 2/28 recurrence (the second attack was infected with influenza type B) improve, 2/28 death

7/7 improve including: 1/7 recurrence (the second attack was infected with influenza type A) improve