Chronic tonsillitis, characterized by persistent infection and inflammation of the palatine tonsils, is a prevalent condition in paediatric populations and a major contributor to morbidity in developing regions [1,2]. Palatine tonsils are important mucosa-associated and immunocompetent lymphoid organs located close to the respiratory and gastrointestinal tracts, which are teeming with microorganisms [3]. The palatine tonsils could protect the body from the entry of exogenous material through mucosal sites. This condition also enables the passage of microorganisms through the epithelium, which attacks the immune system and causes tonsillar diseases [4,5]. Although the clinical criteria for CT and TH have been published, the potential biomarkers to identify CT patients from TH patients and the pathogenesis behind the diseases are still under investigation [6]. The palatine tonsils are lymphoid organs that function as frontline immune barriers, yet chronic infection fosters biofilm formation within the tonsillar crypts, promoting microbial persistence and antibiotic resistance [7]. The aetiology of chronic tonsillitis is often polymicrobial: while Streptococcus pyogenes has long been implicated, increasing evidence highlights the prominent role of Staphylococcus aureus and Haemophilus influenzae in recurrent infections [8,9]. Molecular studies have revealed highly diverse tonsillar microbiota, including anaerobic species such as Fusobacterium necrophorum, which have been linked to recurrent disease and severe complications [10,11]. Systemically, chronic tonsillitis induces an inflammatory response detectable in peripheral biomarkers. Serum ferritin, an iron-binding acute-phase protein, is significantly elevated in various chronic infections and has been correlated with disease activity [12,13]. Concurrently, complete blood count (CBC) indices, particularly total white blood cell (WBC) count and neutrophil percentage, often exhibit mild to moderate elevations in tonsillar disease, though records on associated lymphocyte changes remain inconsistent [14-16]. Despite these associations, research correlating specific tonsillar bacterial profiles with serum ferritin and CBC parameters in paediatric chronic tonsillitis remains limited, especially within Iraq. This study aims to (1) delineate the bacterial colonization patterns in the tonsils of Iraqi children with chronic tonsillitis and (2) investigate the relationships between identified pathogens and systemic inflammatory markers such as serum ferritin and WBC indices.

This cross-sectional observational study was conducted by a team of board-certified otolaryngologists (ENT specialists) in private ENT clinics throughout Kirkuk City, Iraq. The study period extended from June 1, 2023, to December 31, 2024. It was designed to evaluate the relationship between tonsillar bacterial flora and systemic inflammatory biomarkers (serum ferritin and white blood cell indices) in paediatric patients diagnosed with chronic tonsillitis.

Fifty paediatric patients (aged <12 years) presenting with chronic tonsillitis and scheduled for elective bilateral tonsillectomy were enrolled. All participants underwent a thorough ENT evaluation, including otoscopic examination and nasopharyngoscopy when indicated.

Inclusion Criteria

• Age less than 12 years

• Clinical diagnosis of chronic tonsillitis (recurrent sore throat ≥5 episodes/year)

• No antibiotic therapy during the 7 days prior to surgery

• Informed consent provided by parents or legal guardians

Exclusion Criteria

• Acute tonsillitis at time of surgery

• Recent antibiotic use (<7 days before surgery)

• Known immunodeficiency or autoimmune disorders

• Coexisting chronic illnesses (e.g., malignancy, metabolic syndromes)

Surgical Procedure and Tissue Collection

All tonsillectomies were performed under general anaesthesia by experienced ENT surgeons using either cold dissection or bipolar electrocautery, depending on intraoperative assessment. The excised palatine tonsils were immediately transferred to sterile containers and transported to the microbiology lab within 30 minutes under temperature-controlled conditions (4-8°C). Particular care was taken to sample the core tissue to minimize surface contamination.

Microbiological Procedures

Tonsillar tissue samples were processed by homogenization and inoculation onto the following media:

• Blood agar for Gram-positive cocci

• MacConkey agar for Gram-negative organisms

• Chocolate agar for fastidious respiratory flora

Plates were incubated at 37°C for 24-48 hours under aerobic and microaerophilic conditions. Bacterial isolates were identified based on colony morphology, Gram staining and standard biochemical tests (catalase, coagulase, oxidase). When needed, automated systems were used to confirm identification.

Antibiotic Sensitivity Testing

The antimicrobial susceptibility of isolated organisms was determined by the Kirby-Bauer disk diffusion method following CLSI (Clinical and Laboratory Standards Institute) guidelines. Results were interpreted in collaboration with microbiologists and ENT clinicians to ensure clinical relevance.

Haematological and Biochemical Analysis

Preoperative peripheral venous blood samples (5 mL) were collected aseptically. Laboratory analyses included:

• Serum Ferritin: Measured using paediatric ELISA kits (normal range: 12-100 ng/mL)

• Complete Blood Count (CBC): Including WBC count, neutrophil percentage and lymphocyte percentage, assessed using an automated haematology analyser

Statistical Analysis

All data were entered and analysed using SPSS version 25. Continuous variables were expressed as mean ± standard deviation and categorical data as frequencies and percentages. Pearson’s correlation coefficient (r) was used to assess the relationship between serum ferritin and WBC indices. Logistic regression was performed to identify predictors of elevated ferritin levels. A p-value < 0.05 was considered statistically significant.

The study population included 50 children (under 12 years) undergoing tonsillectomy for chronic tonsillitis. The mean age was 8.3 ± 2.4 years. A male predominance was noted (56%), with a male-to-female ratio of approximately 1.3:1. Most participants (72%) resided in urban areas, likely reflecting both referral patterns and healthcare access in Kirkuk city (Table 1).

The data on bacterial identification highlights that Streptococcus pyogenes was the predominant pathogen, isolated in 20 cases (40%), indicating its major role in the infections studied. Staphylococcus aureus followed with a significant proportion of 15 cases (30%), while Haemophilus influenzae and Moraxella catarrhalis were less frequently detected, accounting for 16% and 10% of cases, respectively. Notably, 2 cases (4%) yielded sterile cultures, suggesting either prior antibiotic use or non-bacterial aetiologies (Table 2 and Figure 1).

Susceptibility testing demonstrated that ceftriaxone had the highest overall sensitivity rate (88%), followed by ciprofloxacin (82%) and amoxicillin-clavulanate (76%). Azithromycin had the lowest sensitivity (64%), indicating emerging resistance. These findings suggest that empirical treatment protocols should be revisited in light of evolving resistance patterns in chronic tonsillar flora (Table 3).

Correlation analysis (Table 4) revealed a statistically significant moderate positive correlation between serum ferritin and total WBC (r = 0.52, p < 0.01) and between ferritin and neutrophil percentage (r = 0.47, p < 0.05). No significant correlation was found with lymphocyte count (r = -0.12).

The haematological profile (Table 5) showed elevated WBC counts (mean: 10.4 ± 2.1 ×10⁹/L), with a predominance of neutrophils (62.3 ± 8.6%), supporting the diagnosis of low-grade bacterial inflammation. Lymphocyte percentages were within expected paediatric ranges.

Patients with Staphylococcus aureus infections had the highest mean ferritin levels (134.6 ± 18.2 ng/mL), followed by S. pyogenes (118.4 ± 15.7 ng/mL). These levels were significantly higher than those found in children with negative cultures (68.5 ± 9.3 ng/mL), suggesting that certain pathogens may provoke a stronger systemic inflammatory response (Figure 2).

Multivariate logistic regression analysis revealed that S. aureus infection was independently associated with elevated ferritin levels (OR = 3.25, p = 0.02). Additionally, neutrophilia (>65%) was also a significant predictor (OR = 2.89, p = 0.03), further supporting the role of this organism in driving systemic inflammation (Figure 3).

Table 1: Demographic Characteristics of the Study Population

Table 2: Bacterial Isolates from Tonsillar Tissue

This study offers valuable insight into paediatric chronic tonsillitis with reference to microbial profiles and systemic inflammation in a Kirkuk cohort. The average age of 8.3 ± 2.4 years aligns with established paediatric ENT data, while the slightly higher prevalence among males (56%) is consistent with regional epidemiology [1,11,17]. The predominance of urban residents (72%) likely reflects healthcare access biases rather than actual disease distribution. Microbiological analysis showed Streptococcus pyogenes was the predominant pathogen, isolated in 20 cases (40%), indicating its major role in the infections studied. Staphylococcus aureus followed with a significant proportion of 15 cases (30%). These findings are concordant with earlier studies such as Yildirim et al. [2] and Brook [1], reinforcing their role in recurrent tonsillitis. The involvement of Haemophilus influenzae and Moraxella catarrhalis confirms the polymicrobial nature typical in chronic infections [3,4]. Notably, the persistence of intracellular or biofilm-embedded S. aureus has been documented [5,15] and our data lends further support to this pathological mechanism. Antimicrobial susceptibility patterns revealed high efficacy for ceftriaxone (88%) and ciprofloxacin (82%), while amoxicillin-clavulanate was slightly less (76%). Alarmingly, macrolide sensitivity for azithromycin was only 64%, pointing to rising antibiotic resistance.

Figure 1: Bacterial Isolates from Tonsillar Tissue

Table 3: Antibiotic Sensitivity of Isolates

Table 4: Serum Ferritin Distribution

Table 5: White Blood Cell Indices

Table 6: Predictors of Elevated Ferritin Levels (>100 ng/mL)

Figure 2: Correlation between Serum Ferritin and WBC Indices

Figure 3: Serum Ferritin Levels by Bacterial Species

 These findings prompt reconsideration of standard treatment protocols given the regional emergence of macrolide-resistant strains [6,18,19]. Serum inflammatory marker analysis showed elevated ferritin (>100 ng/mL) in 60% of participants, indicative of ongoing low-grade inflammation. This observation echoes the work of Al Azzawi [8] and Al‑Rubaye [9], who documented similar ferritin increases in chronic tonsillitis. Additionally, WBC counts (10.4 ×10⁹/L) with predominant neutrophilia (62%) align with earlier findings that correlate chronic tonsillar infection with elevated cellular inflammation [8,10,12]. Statistical analysis showed moderate but significant correlations between ferritin and total WBC (r = 0.52, p <0.01), as well as ferritin and neutrophil percentage (r = 0.47, p <0.05). These correlations reinforce the concept of ferritin as an acute-phase reactant tied to systemic immune activity and echo findings from Kernan & Carcillo [7] and Ahmed et al. [14]. Children harbouring S. aureus exhibited markedly higher ferritin levels (mean 134.6 ng/mL) versus culture-negative peers (68.5 ng/mL). Zuliani et al. [5] previously highlighted the pathogenicity of intracellular S. aureus, which our results corroborate. Regression analysis confirmed S. aureus infection (OR 3.25, p=0.02) and neutrophilia >65% (OR 2.89, p=0.03) as independent predictors of elevated ferritin, emphasizing the combined influence of pathogen virulence and host response. The clinical implications are clear: ferritin and WBC measurements represent accessible, cost-effective ancillary tools that complement microbiological data. Elevated biomarkers in the presence of S. aureus may justify earlier surgical referral rather than prolonged antibiotic therapy. These findings resonate with broader ENT management principles, such as those by Brandtzaeg [10] and Sancho‑Shimizu & Brodin [11]. However, this study has limitations. Its single-centre nature and sample size of 50 limit wider applicability. Absence of biofilm-specific assays, molecular pathogen detection and additional markers such as CRP or ESR are acknowledged constraints [20-22]. Future multi-site investigations employing molecular techniques, biofilm characterization and ferritin-guided treatment trials would be valuable.

Chronic tonsillitis in children is frequently associated with S. pyogenes and S. aureus, which provoke elevated systemic inflammatory markers. Correlating serum ferritin with WBC indices offers valuable insight into disease severity and could guide clinical decision-making.

Ethical Approval

This study was approved by the Ethical Review Board of the Kirkuk Health Directorate. Written informed consent was obtained from parents or guardians of all participants. All procedures conformed to the ethical principles outlined in the Declaration of Helsinki.

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