Anemia is a global public health problem affecting both developed and developing nations, with a disproportionately higher burden in low- and middle-income countries. According to the World Health Organization (WHO), anemia is defined as a hemoglobin concentration of less than 13 g/dL in adult males, less than 12 g/dL in adult females, and less than 11 g/dL in pregnant women¹. The etiology of anemia is multifactorial, encompassing nutritional deficiencies, chronic infections, inflammatory disorders, bone marrow dysfunction, and inherited hematological conditions².

In India, anemia continues to pose a significant health challenge across all age groups, particularly among women of reproductive age, children, and elderly individuals³. Nutritional deficiencies such as iron, vitamin B12, and folate deficiency are predominant contributors, while anemia of chronic disease is increasingly recognized in patients with chronic infections, malignancies, renal disease, and autoimmune disorders⁴. The clinical presentation of anemia varies widely, ranging from asymptomatic laboratory findings to severe manifestations such as fatigue, dyspnea, palpitations, cognitive impairment, and cardiovascular compromise⁵.

The morphological classification of anemia based on red blood cell indices and peripheral blood smear examination provides valuable clues to the underlying pathophysiology. Microcytic hypochromic anemia is commonly associated with iron deficiency and thalassemia, normocytic normochromic anemia is often linked to chronic disease and acute blood loss, while macrocytic anemia is typically seen in vitamin B12 or folate deficiency⁶. Peripheral smear evaluation remains a cornerstone in anemia diagnosis, especially in resource-limited settings, allowing visualization of red cell morphology, anisopoikilocytosis, and associated leukocyte or platelet abnormalities⁷.

Clinicopathological correlation integrates clinical findings with laboratory and pathological data, enabling accurate diagnosis and targeted treatment. This approach is particularly important in tertiary care centers where patients often present with complex, multisystem disorders⁸. Despite advances in automated hematology analyzers, peripheral smear examination and clinical correlation continue to play a vital role in differentiating various anemia patterns⁹.

The present study was undertaken to evaluate the spectrum of anemia patterns in a tertiary care hospital and to correlate clinical presentations with hematological and pathological findings. Understanding these correlations can aid clinicians in early diagnosis, appropriate investigations, and effective management strategies, thereby reducing morbidity associated with anemia¹⁰.

This was a hospital-based, cross-sectional observational study conducted in the Departments of Pathology and General Medicine at a tertiary care teaching hospital over a period of 18 months.

Study Population

All patients aged ≥18 years presenting to outpatient or inpatient services and diagnosed with anemia during the study period were considered for inclusion.

Inclusion Criteria

• Patients aged 18 years and above
• Hemoglobin levels below WHO-defined cut-off values
• Patients who consented to participate in the study
• Availability of complete hematological and clinical data

Exclusion Criteria

• Patients who received blood transfusion within the previous 3 months
• Pregnant women
• Patients with acute hemorrhage or trauma
• Incomplete laboratory or clinical records

Data Collection

Detailed clinical history including demographic profile, dietary habits, socioeconomic status, presenting symptoms, comorbidities, and drug history was recorded. Physical examination focused on pallor, icterus, lymphadenopathy, hepatosplenomegaly, and signs of chronic disease.

Laboratory Evaluation

Venous blood samples were collected under aseptic precautions. Hematological parameters including hemoglobin, red blood cell indices (MCV, MCH, MCHC), total leukocyte count, and platelet count were analyzed using an automated hematology analyzer. Peripheral blood smears were prepared and stained with Leishman stain for morphological assessment.

Additional investigations such as serum ferritin, vitamin B12, folate levels, renal function tests, liver function tests, and bone marrow examination were performed where clinically indicated.

 Classification of Anemia

Anemia was classified morphologically into:

• Microcytic hypochromic
• Normocytic normochromic
• Macrocytic
• Dimorphic

 Statistical Analysis

Data were entered into Microsoft Excel and analyzed using SPSS software. Categorical variables were expressed as frequencies and percentages, while continuous variables were expressed as mean ± standard deviation. Chi-square test was used to assess associations, with a p-value <0.05 considered statistically significant.

Table 1. Demographic Distribution of Study Population (n = 300)

Anemia was more prevalent among males, with maximum cases in the middle-aged population.

Table 2. Severity of Anemia

Moderate anemia constituted the majority of cases.

Table 3. Morphological Patterns of Anemia

Microcytic hypochromic anemia was the predominant pattern.

Table 4. Etiological Distribution

Nutritional anemia remained the most common cause.

Table 5. Clinical Features Associated with Anemia

Fatigue was the most frequent presenting symptom.

Table 6. Clinicopathological Correlation

Strong correlation was observed between morphological patterns and underlying clinical etiologies.

The present study highlights the spectrum of anemia patterns encountered in a tertiary care setting and emphasizes the importance of clinicopathological correlation. Microcytic hypochromic anemia emerged as the most prevalent morphological type, accounting for nearly half of the cases. This finding aligns with multiple Indian and international studies that identify iron deficiency as the leading cause of anemia, particularly in populations with poor nutritional intake and chronic blood loss¹¹,¹².

Normocytic normochromic anemia constituted approximately one-third of cases and was predominantly associated with chronic inflammatory conditions, renal disease, and malignancies. Similar observations have been reported by previous studies, underscoring the role of inflammatory cytokines and impaired erythropoiesis in anemia of chronic disease¹³,¹⁴.

Macrocytic anemia accounted for 14% of cases, commonly associated with vitamin B12 and folate deficiency. Neurological manifestations were frequently noted in this group, reinforcing the clinical significance of early diagnosis and treatment¹⁵. The proportion of macrocytic anemia observed in this study is comparable to reports from other tertiary care centers¹⁶.

Dimorphic anemia, though less common, reflected mixed nutritional deficiencies, highlighting the coexistence of iron and vitamin B12 or folate deficiency, particularly in elderly and malnourished patients¹⁷.

The strong correlation between clinical features and morphological patterns underscores the value of peripheral smear examination. Despite advancements in automated diagnostics, smear evaluation remains indispensable for detecting subtle morphological changes and guiding further investigations¹⁸.

Our findings are consistent with studies by Kumar et al. and Sharma et al., which demonstrated similar anemia distribution patterns and emphasized the relevance of clinicopathological correlation in routine practice¹⁹,²⁰. The study reinforces the need for comprehensive anemia evaluation in tertiary care hospitals, where patients often present with complex clinical backgrounds.

Early identification of anemia etiology not only improves patient outcomes but also reduces unnecessary investigations and healthcare costs. Integrating clinical assessment with hematological and pathological findings remains the cornerstone of effective anemia management²¹,²².

Anemia remains a significant clinical problem with diverse etiologies. Microcytic hypochromic anemia due to iron deficiency is the most common pattern encountered in tertiary care settings. Clinicopathological correlation, supported by peripheral smear examination, plays a crucial role in accurate diagnosis and management. A systematic approach integrating clinical features and laboratory findings is essential for effective patient care.

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