Filariasis on cytology of clinically unsuspected sites trapped accidentally on aspiration – A challenge ahead.

Richa Bhartiya; Pallavi Mehra; Vishal Tayade; Dipika Bongale; Manasi Karwa; Navin Kumar Bariar

doi:10.51168/sjhrafrica.v7i2.2805

Authors

Dr. Richa Bhartiya Associate Professor, Department of Pathology, Grant Government Medical College and Sir JJ Group of Hospitals, Mumbai, Maharashtra, India
Dr. Pallavi Mehra Associate Professor, Department of Pathology, Patna Medical College & Hospital, Patna, Bihar, India.
Dr. Vishal Tayade Assistant Professor, Department of Pathology, Grant Government Medical College and Sir JJ Group of Hospitals, Mumbai, Maharashtra, India.
Dr. Dipika Bongale Junior Resident, Department of Pathology, Grant Government Medical College and Sir JJ Group of Hospitals, Mumbai, Maharashtra, India.
Dr. Manasi Karwa Junior Resident, Department of Pathology, Grant Government Medical College and Sir JJ Group of Hospitals, Mumbai, Maharashtra, India.
Dr. Navin Kumar Bariar Professor and Ex-HOD, Pathology, Department of Pathology, Patna Medical College & Hospital, Patna, Bihar, India

DOI:

https://doi.org/10.51168/sjhrafrica.v7i2.2805

Keywords:

Wuchereria bancrofti, lymphatic filariasis, fine-needle aspiration cytology, microfilaria, incidental diagnosis, cytopathology, occult filariasis

Abstract

Background

Incidental detection of microfilariae in fine-needle aspiration cytology (FNAC) specimens from clinically unsuspected sites is uncommon but clinically important, particularly in filariasis-endemic regions. This study evaluated the clinicopathological spectrum of incidental filariasis detected on FNAC and highlighted the diagnostic utility of cytology in identifying occult infections.

Materials and Methods

This retrospective observational study included 33 cases of incidental microfilarial detection on FNAC diagnosed at the Department of Pathology, Patna Medical College and Hospital, India, between January 2012 and January 2022. Clinical details, anatomical sites, cytomorphological findings, peripheral blood smear results, and eosinophil counts were reviewed. Cases with peripheral blood microfilaremia were excluded.

Results

Thirty-three patients (20 males and 13 females; age range: 12–80 years) were studied. Microfilariae were detected in subcutaneous swellings (n=8), breast lesions (n=7), lymph nodes (n=7), liver lesions (n=4), mediastinal masses (n=2), and single cases involving the thyroid, lung, gallbladder, periampullary region, and parietal wall. None of the patients had clinical suspicion of filariasis before cytological examination. Eight cases were associated with malignant lesions, while the remainder occurred with benign or inflammatory conditions. Peripheral blood smears were negative in all cases, and eosinophilia was present in only seven patients.

Conclusion

FNAC is a rapid, minimally invasive, and cost-effective modality for detecting occult filariasis at clinically unsuspected sites. Microfilariae may coexist with a wide range of benign and malignant lesions even in the absence of peripheral microfilaremia or eosinophilia.

Recommendation

Routine and meticulous screening of all cytology smears for microfilariae is recommended in endemic regions irrespective of clinical suspicion, as early detection facilitates timely treatment and appropriate management of associated lesions.

Author Biographies

Dr. Richa Bhartiya , Associate Professor, Department of Pathology, Grant Government Medical College and Sir JJ Group of Hospitals, Mumbai, Maharashtra, India

is Associate Professor in the Department of Pathology at Grant Government Medical College and Sir JJ Group of Hospitals, Mumbai, with research interests in cytopathology and diagnostic pathology.

Dr. Pallavi Mehra, Associate Professor, Department of Pathology, Patna Medical College & Hospital, Patna, Bihar, India.

is Associate Professor in the Department of Pathology at Patna Medical College and Hospital, Patna, with special interest in cytopathology and hematopathology.

Dr. Vishal Tayade, Assistant Professor, Department of Pathology, Grant Government Medical College and Sir JJ Group of Hospitals, Mumbai, Maharashtra, India.

is Assistant Professor in the Department of Pathology at Grant Government Medical College and Sir JJ Group of Hospitals, Mumbai, with expertise in diagnostic pathology.

Dr. Navin Kumar Bariar, Professor and Ex-HOD, Pathology, Department of Pathology, Patna Medical College & Hospital, Patna, Bihar, India

is Professor and former Head of the Department of Pathology at Patna Medical College and Hospital, Patna, with extensive experience in academic pathology and medical education.

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