Surgical Site Infection in Minor Diabetic Amputation in Solomon Islands: A three-year retrospective study

Authors:
Benjamin J. Katz, Taylor R. Robinson, Dylan Bush, Stallone Kohia, Raymond Dickson, Alfram Vakimuna, Rooney Jagilly, Ruhul Abid

Body of Abstract:
Introduction: Solomon Islands, a Western Pacific nation of nearly 1,000 islands, faces a rapidly rising burden of type II diabetes, affecting close to one-fifth of adults. Limited access to medical care outside the capital, Honiara, and frequent delays in seeking treatment contribute to advanced diabetic foot infections that often progress to limb-threatening disease.

Minor amputations, such as toe or forefoot procedures, offer an important limb-salvaging intervention and may preserve mobility if performed early. While outcomes of diabetic foot surgery are well described in high-income settings, little is known about microbiologic patterns and postoperative trajectories in geographically remote Pacific Island nations. This study characterizes microbiologic profiles surrounding minor diabetic amputations in Solomon Islands and examines their associations with clinical status, therefore informing management strategies in similar low-resource tropical settings.

Methods: This three-year retrospective study (2020-2022) included patients who underwent minor limb amputations for diabetes-related infections at two hospitals, redacted. Patients were identified from surgical logbooks, and data were collected through chart review under an IRB-approved protocol.

Results: A total of 119 patients underwent minor diabetic amputations during the study period, with microbiologic data available for 63 cases. Patients were majority male (62.4%, n = 73), with 46 females (37.6%, n=46). Polymicrobial infection was common: 15 patients (24%) had one organism identified, 17 (27%) had two organisms, and nearly half of all patients (31, 49%) had three organisms, the maximum number recorded. Gram-negative bacilli were the most frequently identified group (n=37), followed by Gram-positive cocci (n=23), Gram-positive bacilli (n=6), and Gram-negative cocci (n=5). Specific pathogens included P. aeruginosa (n=14), K. pneumoniae (n=6), S. aureus (n=9), E. coli (n=3), and various Proteus species.

When infection patterns across all three microbiology fields were analyzed in combination, no association with gender was observed. Most laboratory parameters did not differ by infection profile; however, platelet count (p = 0.029) and white blood cell count (p = 0.041) varied significantly, with more complex infection patterns associated with higher inflammatory markers. Serum potassium (p = 0.052) and sodium (p = 0.082) showed borderline differences.

Conclusion: These findings suggest that complex, multidimensional infection patterns may correspond to varying degrees of systemic inflammation at presentation, a dynamic particularly relevant in tropical LMIC settings like Solomon Islands. Delayed care and limited wound management resources may have contributed to advanced, polymicrobial disease in patients with minor diabetic amputations. Therefore, understanding the risk and rate of microbial infection in these populations is paramount to improving post-operative outcomes.