Objective: To analyze the clinical characteristics

inflammatory and immune indicators in children with severe adenovirus pneumonia. Methods: Clinical characteristics and immune indicators of 91 children with adenovirus pneumonia diagnosed in Hunan Children’s Hospital from Jun. 2018 to Dec. 2019 were retrospectively analyzed. According to the severity of disease

all children were divided into 49 cases in the severe adenovirus pneumonia group (severe group) and 42 cases in the non-severe adenovirus pneumonia group (non-severe group). According to the occurrence of bronchiolitis obliterans (BO)

children in the severe group were divided into the BO group and the non-BO group. All children were given symptomatic supportive treatment such as cough and sputum relief

wheezing relief and rehydration

and anti-infection treatment was given to those children with co-infection or high risk factors. Patients in the severe group were treated with gamma globulin

ventilator-assisted ventilation

methylprednisolone anti-inflammatory and blood purification to remove inflammatory mediators. Results: Adenovirus pneumonia mostly occurred in children <5 years old

accounting for 86.8% (79/91)

and the mortality rate was 5.5% (5/91)

of which 46.2% (42/91) were severe. The younger the children

the more severe the condition

the higher the mortality rate

the greater the number of cases requiring mechanical ventilation and BO

and the longer the length of hospitalization and ICU stay (P<0.05). In the severe group

71.4% (30/42) were given anti-infection treatment

54.8% (23/42) were given gamma globulin immunotherapy

47.6% (20/42) required mechanical ventilation and alveolar lavage

38.1% (16/42) were given methylprednisolone to inhibit the inflammatory response of the body

and 19.0% (8/42) underwent blood purification to remove inflammatory mediators. The mortality rate was 11.9% (5/42)

and BO occurred in 23.8% (10/42). The levels of white blood cell count (WBC)

neutrophil count (N)

C-reactive protein (CRP)

erythrocyto sedimentation rate (ESR)

proealcitonin (PCT)

immunoglobulin E (IgE) and interleukin 6 (IL-6) in the severe group were higher than those in the non-severe group

and the lymphocyte subsets and immune indicators (except for IgM) were lower than those in the non-severe group (P<0.05). The levels of WBC

N

CRP

IgE and IL-6 in the BO group were higher than those in the non-BO group

while the levels of B lymphocytes

CD3+

CD4+

Th/Ts

C3 and IgA were lower than those in the non-BO group (P<0.05). The level of neutrophil in bronchoalveolar lavage fluid in the BO group was higher than that in the non-BO group (P<0.05). Conclusion: Children with severe adenovirus pneumonia have the strong inflammatory and immune dysfunction

with higher mortality rate

and it is easy to prone to BO. Clinical monitoring of inflammatory and immune parameters should be carried out at an early stage

so that interventions and comprehensive treatment such as immune support therapy and inhibition or removal of inflammatory factors can be carried out as early as possible

and emphasis should be placed on BO prevention and treatment to improve the prognosis.