Table 5.

Retrospective Studies on Children Including Children With Protracted Bacterial Bronchitis

First author, publication year; country	Setting; study design	Definition of PBB used	No. in study; age	Main aim(s)	Key finding(s)	Specimen; microbiology	Other main findings	Comment
Donnelly [2007],43 England	Resp OPD; review of clinic letters (random)	Persistent, wet cough present for 1 mo that resolved with “appropriate” AB treatment	81; median = 3.8 yrs (range 0.4–14.8)	Review the outcomes in 81 randomly selected patients diagnosed with PBB	95% cured with AB use; 48% reported “wheeze,” but had a “ruttle” instead	BAL (n = 19), cough swab (n = 51). Of infected specimens (∼50%): Hi = 81%, Spn = 37%	59% symptomatic for >1 yr; bronchiectasis in 4/14 who had chest CT scan; 31% with concomitant “asthma” (BDR demonstrated or responsive to steroids)	Not all children had PBB based on original definition of PBB
Kompare [2011],19 USA	Resp and allergy OPD	Cough, wheeze or noisy breathing for >1 mo without other diagnoses, BAL (≥104 CFU/ml) and response to ≥2 wks AB treatment	70; summary age NR	Review all BAL (≥104 CFU/ml) cultures of children aged <5 yrs with cough, wheeze, or noisy breathing for >1 mo without other diagnoses so as to determine if PBB was present	Tracheo‐ or broncho‐malacia present in 74%	BALHi = 56%, Spn = 37%; Mcat = 59%	Outcome data (available in 87%): symptoms resolved with AB treatment in all but one child	Bronchitis itself may cause malacia
Priftis [2013],42 Greece and England	Resp OPD	Children with chronic cough suspected of PBB who had FB to confirm diagnosis	Greece = 18, England = 39; median age = 4.8 yrs (range 0.9–14.4)	To (a) determine specific serotypes of Spn and NTHi in BAL samples and (b) compare Spn serotypes between the two countries and Spn vaccination	PCV‐13 Spn serotypes in all Greek BALs, but only in 72% of English BALs (significantly different b/w countries)	Greek BAL; Hi = 61%, Spn = 27.6%; Mcat = 32%; Sa = 6%; English BAL restricted to Spn+ specs	Vaccine Spn serotypes rarely found in immunized children (OR = 0.02; 95%CI 0.003–0.115); 26 NTHi isolates (English BAL) had unique genotypes	Recent or current AB use NR. Evidence of serotype replacement disease in Spn‐immunized children
Narang [2014],62 England	Pediatric and Resp OPD; 50 consecutive notes	Suspected PBB (ND)	50; median age = 2.9 yrs (IQR 1.7, 4.4)	Review BAL and chest radiograph results, and assess the bacterial distribution across lung lobes	Bacterial distribution in PBB was heterogeneous	BAL; Hi = 50%, Spn = 16%, Mcat = 28%, Sa = 22%	Limiting sampling to 1–2 lobes will under‐estimate the microbiology of the lung (70% positive vs. 82%)	Positive culture undefined as quantitative culture was not done
Pritchard [2014],55 England	Pediatric and Resp OPD	AB responsive wet cough and positive BAL culture	43; median = 2.7 yrs (IQR 1.5, 4)	Review of treatment outcomes for children with PBB	Cough resolved in 77% after initial AB course (6–8 wks) but only 24% remained cough free (i.e., 76% relapsed)	BAL; Hi = 63%, Spn = 23%, Mcat = 51%, Sa = 19%	Of the 10 whose cough did not resolve after 6–8 wks ABs, 7 required prolonged ABs and 3 had other resp conditions	BE more likely to be present when wet cough unresponsive to 4 wks of ABs.49 Thus, likely some in cohort did not have PBB

ABs, antibiotics; AdV, human adenovirus; Amox‐clav, amoxicillin‐clavulanate; BAL, bronchoalveolar lavage; BE, bronchiectasis; BDR, bronchodilator responsive, btw, between, CF, cystic fibrosis, CFU, colony‐forming units, CSLD, chronic suppurative lung disease; CT, computed tomography, CXCR2, chemokine (C‐X‐C Motif) receptor 2, Dx, diagnosis, Exc, exclusion criteria, Exp, experimental; FB, flexible bronchoscopy; FU, follow‐up; hBD2, human β‐defensin‐2; Hi, Haemophilus influenzae, Hib, Haemophilus influenzae type b, IL, interleukin; IQR, interquartile range, MBL, mannose‐binding lectin; Mcat, Moraxella catarrhalis, MMP, matrix metalloproteinase, mo, months, mRNA, messenger RNA, ND, not described, NF‐κB, nuclear factor kappa‐light‐chain‐enhancer of activated B cells, NK, natural killer cell, No, number, NR, not reported, NTHi, nontypeable Haemophilus influenzae, OPD, outpatient department, OR, odds ratio, PBB, protracted bacterial bronchitis, PC‐QOL, parent cough‐specific quality of life, PCV‐13, 13 serotype pneumococcal conjugate vaccine; PedQL, pediatric quality of life, Pros, Prospective; RAST, radioallergosorbent test, RCT, randomized controlled trial, Resp, respiratory, Retro, retrospective; Sa, Staphylococcus aureus, SD, standard deviation, SP‐A, Surfactant protein‐A; Spn, Streptococcus pneumoniae, *SR, spontaneous resolution (defined below), TLR, toll‐like receptor; TNF, tumor necrosis factor, wk, weeks; yr, year.

*Spontaneous resolution (SR) defined as resolution of cough without therapy or, if this was tried the cough resolved more than 2 weeks after ceasing treatment.