Acute pancreatitis (AP) is a rapid inflammation of the pancreas that can affect nearby tissues and other organ systems.1 The clinical manifestation varies from mild, self-limiting inflammation to severe, necrotizing disease characterized by considerable morbidity and mortality.2 Over the past few decades, the number of people with AP around the world has been going up. This is mostly because to changes in lifestyle, drinking too much alcohol, and gallstone disease. Finding people who are likely to get severe pancreatitis early on is very important. This is because quick intervention and close monitoring can greatly lower complications and improve outcomes.3

Pathophysiologically, AP commences with the early activation of pancreatic enzymes in the acinar cells, resulting in autodigestion, inflammation, and cellular damage. If this localized inflammation isn't caught early, it could turn into a systemic inflammatory response syndrome (SIRS), which could cause problems in many organs.4,5

The Revised Atlanta Classification (2012) divides the condition into mild, moderately severe, and severe types based on organ failure and local or systemic consequences. Mild pancreatitis normally gets better with simple treatment, while severe pancreatitis often needs urgent care and has a high death rate of up to 30%.6

The severity of the disease can be predicted using a variety of scoring systems, including APACHE II, Glasgow score, BISAP, and Ranson's criteria. These methods are useful, but they have certain problems. For example, they are hard to use, need more than one lab parameter, and take time to become predictive. So, we need a biomarker that is easy to use, quick, and cheap that can tell us how bad AP is going to be early on.7, 8

The neutrophil-to-lymphocyte ratio (NLR), obtained from a standard complete blood count, has surfaced as a potential inflammatory biomarker. Neutrophils are very important in the acute inflammatory response because they release cytokines and reactive oxygen species. Lymphocytes, on the other hand, are the immune system's regulating arm.9

A high NLR means that the body is moving toward a pro-inflammatory condition. This is often seen in severe infections, sepsis, cardiovascular illnesses, cancers, and other inflammatory disorders. In AP, the level of systemic inflammation is linked to how bad the disease is, which means that NLR could be a sign of how the condition will progress.10

Recent study data indicates that an elevated NLR at admission correlates with severe acute pancreatitis (SAP), organ failure, and an extended duration of hospitalization. NLR may be estimated from standard blood tests that are available everywhere. This makes it a quick, cheap, and repeatable marker, especially in healthcare settings where resources are limited.11 Its simplicity lets doctors quickly put patients into risk groups early in the disease process, which makes it easier to send them to higher facilities or keep a close eye on them as needed. This study seeks to enhance risk assessment and facilitate prompt, evidence-based therapy in patients with AP by identifying NLR as an early prognostic indicator.

AIMS AND OBJECTIVES

• To evaluate the role of the neutrophil-to-lymphocyte ratio in predicting the severity of acute pancreatitis and to correlate its value with clinical outcomes.

This was a prospective observational study conducted in the Department of General Surgery, Sree Mookambika Institute of Medical Sciences, Kulasekharam, over a period of 12 months from June 2024 to May 2025. A total of 45 patients admitted to the surgical wards and intensive care unit (ICU) with a diagnosis of AP were included in the study after obtaining informed consent. All patients were evaluated clinically, biochemically, and radiologically according to institutional protocols. Inclusion Criteria 1. Patients aged 18 years and above diagnosed with AP. 2. Diagnosis confirmed by two or more of the following criteria (based on the Revised Atlanta Classification, 2012): 3. Characteristic abdominal pain consistent with AP. 4. Serum amylase and/or lipase levels at least three times the upper limit of normal. 5. Imaging findings (ultrasound or CT abdomen) consistent with AP. Exclusion Criteria 1. Patients with chronic pancreatitis or recurrent pancreatitis. 2. Patients with malignancy, autoimmune disorders, or hematological diseases affecting white cell counts. 3. Patients with ongoing infections or those receiving steroids or immunosuppressive therapy. 4. Patients with renal failure, cirrhosis, or severe systemic illness unrelated to pancreatitis. Upon admission, detailed demographic and clinical data were recorded for each patient. Information regarding age, sex, occupation, alcohol consumption, gallstone history, drug intake, and previous attacks of pancreatitis was obtained. A thorough physical examination was conducted to assess abdominal tenderness, guarding, and systemic involvement. Vital signs including pulse rate, blood pressure, respiratory rate, and temperature were documented. The duration of symptoms, severity of abdominal pain, and associated features such as vomiting or abdominal distension were also noted. Laboratory investigations were performed on admission before the initiation of intravenous fluids or antibiotic therapy. Venous blood samples were collected for complete blood count, serum amylase, serum lipase, liver function tests, renal function tests, and serum electrolytes. From the complete blood count, the absolute neutrophil count and absolute lymphocyte count were obtained, and the NLR was calculated by dividing the neutrophil count by the lymphocyte count. Other relevant tests such as C-reactive protein were done when required. Ultrasonography of the abdomen was performed for all patients to identify gallstones, pancreatic enlargement, or peripancreatic fluid collection. In patients with severe clinical presentation or diagnostic uncertainty, contrast-enhanced computed tomography (CECT) of the abdomen was carried out to assess the extent of pancreatic necrosis and local complications. The severity of AP was determined according to the Revised Atlanta Classification (2012). Patients were categorized into mild, moderately severe, and SAP based on the presence and duration of organ failure and the occurrence of local or systemic complications. Mild AP included patients with no organ failure or complications, while moderately severe cases had transient organ failure or localized complications. SAP was diagnosed in patients with persistent organ failure involving one or more organs for more than 48 hours. Additional scoring systems such as the BISAP score and CT severity index were used where applicable to corroborate the severity grading. All patients were managed as per institutional protocols. Initial treatment included aggressive intravenous fluid resuscitation with crystalloids, nil per oral status, and nasogastric decompression in cases with vomiting or paralytic ileus. Analgesics were administered to relieve pain, and antibiotics were prescribed only when infection was suspected or confirmed. Electrolyte imbalances and metabolic abnormalities were corrected promptly. Patients were closely monitored for the development of complications such as hypotension, respiratory distress, renal impairment, or sepsis. Those showing signs of severe disease were transferred to the intensive care unit for advanced monitoring and supportive therapy. The duration of hospital stay, need for intensive care, occurrence of complications, and final outcome were documented for all patients until discharge or death. All collected data were compiled and analyzed using the Statistical Package for the Social Sciences (SPSS) software version 25.0. Continuous variables such as age and NLR were expressed as mean ± standard deviation, while categorical variables such as gender and etiology were presented as frequencies and percentages. Comparisons between groups were made using the independent t-test for continuous variables and the chi-square test for categorical data. Correlation between NLR and severity indices was evaluated using Pearson’s correlation coefficient. The predictive accuracy of NLR for determining severe pancreatitis was assessed by plotting a Receiver Operating Characteristic (ROC) curve to calculate the area under the curve, sensitivity, and specificity at different cut-off levels. A p-value less than 0.05 was considered statistically significant

The majority of patients were in the 41–50 years age group (31.1%), indicating that AP is more common among middle-aged adults. The mean age of presentation was 43.6 ± 11.2 years, suggesting that the disease predominantly affects individuals in their productive age. (Table 1)

Table 1: Age Distribution of Study Population

There was a male predominance (62.2%) in this study, possibly due to the higher prevalence of alcohol consumption among males. (Table 2)

Table 2: Gender Distribution of Study Population

Gallstones were the most common cause of AP (46.7%), followed by alcohol-induced pancreatitis (35.6%). This distribution reflects the local demographic trend where gallstones and alcohol are predominant risk factors. (Table 3)

Table 3: Etiological Factors of Acute Pancreatitis

Out of 45 patients, 22 (48.9%) had mild disease, 13 (28.9%) had moderately severe pancreatitis, and 10 (22.2%) presented with severe disease. Approximately one in five patients developed severe pancreatitis, highlighting the need for early prediction of disease progression. The mean NLR at admission was significantly higher in patients with SAP (14.8 ± 4.3) compared to those with mild or moderate disease (6.7 ± 2.1). The difference was statistically significant (p < 0.001), confirming that a high NLR correlates strongly with disease severity. (Table 4)

Table 4: Severity of Acute Pancreatitis Based on Revised Atlanta Classification

Patients with an NLR ≥ 9.5 had a significantly longer hospital stay, more frequent systemic or local complications, and higher ICU admission rates compared to those with lower NLR values. The results were statistically significant, emphasizing the prognostic value of elevated NLR. (Table 5)

Table 5: Correlation of NLR with Hospital Stay and Complications

The ROC curve analysis revealed an AUC of 0.865, suggesting that NLR is a good predictor of SAP. The optimal cut-off value of 9.5 demonstrated 85% sensitivity and 78% specificity, confirming that NLR is a reliable, cost-effective, and rapid marker for assessing disease severity at admission.

The demographic and clinical characteristics of the study participants were similar to those documented in other regional and worldwide investigations. The average age of presentation was 43.6 ± 11.2 years, with most cases (31.1%) being between 41 and 50 years old. This suggests that AP typically strikes middle-aged people during their most productive years, which can lead to a lot of illness. Pati et al.12 and Vemparala et al.13 have shown similar age distributions, corroborating the global trend that AP predominantly impacts adults in their third to fifth decades of life. The current study exhibited a distinct male predominance, with males constituting 62.2% of the cases. This finding aligns with the studies conducted by Pati et al.12 and Vemparala et al.13, both of which reported a greater prevalence of AP in men. The male predominance may be ascribed to the higher incidence of alcohol usage among males in the Indian population, with alcohol being a prevalent etiological factor for AP. In this study population, gallstones were shown to be the most common cause of AP (46.7%), followed by alcohol-induced pancreatitis (35.6%). The remaining cases were due to hypertriglyceridemia, drugs, or unknown causes. This distribution coincides with recent studies, which identifies gallstones and alcohol as the primary causes of AP globally, but their respective impacts differ by geographic region.12, 13 In the present study, the elevated incidence of biliary pancreatitis relative to alcohol-related illnesses illustrates the regional disparities observed in South Asian populations. According to the Revised Atlanta Classification, 48.9% of patients had mild AP, 28.9% presented with moderately severe disease, and 22.2% progressed to severe acute pancreatitis (SAP) characterized by organ dysfunction or systemic consequences. This distribution is similar to what Bengi et al.14 and Abu-Elfatth et al.15 found, which was that SAP occurred in about 16–19% of cases. The progression of roughly one-fifth of patients in this group to severe disease highlights the clinical significance of early prognostic evaluation to facilitate prompt management. The NLR, a cost-effective and easily quantifiable inflammatory marker, demonstrated a statistically significant association with illness severity (p < 0.001). Higher NLR readings were linked to more severe cases of pancreatitis, which supports the idea that NLR shows the balance between systemic inflammation and physiological stress. Neutrophilia signifies an active inflammatory response, while lymphopenia arises from corticosteroid-induced stress and lymphocyte death, thus enhancing the NLR as an indicator of disease burden. These results corroborate the findings of Vemparala et al.13, who showed that NLR values were markedly elevated and sustained for a longer duration in individuals with SAP compared to those with mild AP. Fonseca et al.16 and Vincent et al.17 also identified strong links between high NLR levels and more severe disease. The second study indicated a strong positive link between NLR and CT Severity Index (r = 0.86, p < 0.001). In the present study, an NLR cut-off value of 9.5 successfully differentiated patients with severe illness. In patients with NLR ≥ 9.5, 55.6% experienced complications and 44.4% necessitated ICU hospitalization, in contrast to 11.1% and 7.4%, respectively, in those with lower NLR values. According to O'Connell et al.18, patients with higher NLR had a higher likelihood of needing to be admitted to critical care or high dependence (p = 0.01). Patients exhibiting elevated NLR values experienced notably extended hospitalizations (9.8 ± 2.6 days versus 5.6 ± 1.4 days), indicating that NLR is associated not only with illness severity but also with morbidity and healthcare consumption. Cifci et al.19 have observed comparable patterns. Receiver operating characteristic (ROC) curve analysis in this study showed an area under the curve (AUC) of 0.865, which means that NLR is a very good predictor of severe illness. At the best cut-off point (NLR = 9.5), the sensitivity was 85% and the specificity was 78%. These results are similar to those found by Kokulu et al.20 (AUC = 0.81, sensitivity 87.5%, specificity 69.1%) and Harsha Vardhan et al.21 (AUC = 0.96, sensitivity 100%, specificity 89%). Overall, these results support the use of NLR as an early, accurate, and low-cost biomarker for diagnosing and predicting the course of AP. Because you may get NLR from a normal complete blood count, it is a useful tool for early risk classification, especially in places where advanced imaging or biochemical scoring methods aren't always available.

The NLR is a robust independent predictor of disease severity in AP. Patients presenting with elevated NLR levels at admission exhibited a greater likelihood of developing AP, necessitating critical care, and experiencing extended hospitalization. NLR can be derived from a straightforward and cost-effective complete blood count, making it a useful complement to clinical and radiological evaluations, especially in environments lacking complex scoring systems or imaging techniques.

FINANCIAL SUPPORT AND SPONSORSHIP

Nil.

CONFLICTS OF INTEREST:

There are no conflicts of interest

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