Original Article [Received: February 9, 2015; accepted after revision: May 18, 2016] Correspondence and reprint requests: Dr Shukla Das, Professor, Department of Microbiology, University College of Medical Sciences (University of Delhi), Guru Teg Bahadur Hospital, Delhi-110 095, India; E-mail: shukladas_123@yahoo.com Introduction Fungal rhinosinusitis (FRS), a disease characterised by fungal colonisation of the nose and para-nasal sinus, has become an increasingly recognised entity over the past decade. It was previously thought to contribute 5% to 15% of all the cases of chronic rhinosinusitis; however later data suggest that the burden of FRS seems to be much more. 1 It is categorised as invasive or non-invasive, based on the presence/absence of fungi in sinus mucosa (submucosa, vessels or bone). The invasive disease includes: (i) acute invasive (fulminant) FRS, (ii) granulomatous invasive FRS, and (iii) chronic invasive FRS. 2 The non-invasive forms include: (i) saprophytic fungal infection, (ii) fungus ball, and (iii) eosinophil related FRS [which includes allergic fungal rhinosinusitis (AFRS), eosinophil fungal rhinosinusitis Clinico-pathological Correlation in Diagnosis of Fungal Rhinosinusitis: A One-Year Study Shukla Das, Arpeeta Mazumdar 1 , Rumpa Saha 1 , S. Sharma 2 , V.G. Ramachandran 1 , N. Gupta 3 and Sajad Dar 1 Departments of Microbiology 1 , Pathology 2 and Otorhinolaryngology 3 , University College of Medical Sciences (University of Delhi) and Guru Teg Bahadur Hospital, Delhi, India Abstract Background. Allergic fungal rhinosinusitis (AFRS), the most common form of fungal rhinosinusitis (FRS) results from an allergy to fungus in immunocompetent patients. There is no consensus on the diagnostic criteria for AFRS and confusion prevails due to difficulty in demonstrating fungal hyphae in the mucin. Methods. We classified patients with FRS (n=30) using various clinical, histopathological and microbiological parameters. The patients underwent computed tomography of nasal and para-nasal sinuses, absolute eosinophil count and testing of serum immunoglobulin E levels. Fungal elements were identified in nasal lavage and polyp samples from 30 patients with chronic rhinosinusitis using potassium hydroxide (KOH), culture, histopathological examination, polymerase chain reaction (PCR) and were categorised into eosinophilic mucin rhinosinusitis, eosinophilic fungal rhinosinusitis, AFRS and fungus ball categories. Results. Allergic fungal rhinosinusitis was evident in 5 (20.8%) patients (EMRS 1; EFRS 4, based on histological examination). Diagnosing the aetiological agent in suspected cases of FRS requires not only a high index of clinical suspicion, but a thorough microbiological and pathological work-up of the samples also and should always be supported by computed tomography findings and immunological work-up for atopy as these not only constitute important diagnostic criteria in cases of AFRS, but also are important pre-operative predictor for the condition. Conclusions. Histopathological examination remains the gold standard for diagnosing chronic FRS but speciation can be possible only with culture or PCR on appropriate samples. The rapid methodology of PCR with appropriate primer pairs has shown promising results in our study and in collaboration with radiological and immunological work-up would provide the complete picture for the diagnosis of FRS. [Indian J Chest Dis Allied Sci 2016;58:225-231] Key words: Chronic rhinosinusitis, Allergic fungal rhinosinusitis, Polymerase chain reaction. (EFRS) and eosinophilic mucin rhinosinusitis (EMRS)]. 2 Allergic fungal rhinosinusitis is the most common form of FRS. 3 It is defined as a condition in an immunocompetent patient with an allergy to fungus. The fungi reside in the mucin and provide continued stimulation causing a hypersensitivity reaction. It is extremely common in India and a rising trend has been noted, but no population-based data are available. 4 The diagnostic criteria for AFRS vary; the Bent and Khun criteria being most widely accepted. 5 However, uncertainity still prevails due to difficulty in demonstrating fungal hyphae in the mucin. The laboratory findings in possible AFRS group can be variable, making the diagnosis quiet controversial. This one-year study is an attempt to classify cases of FRS using various clinical, histopathological and microbiological parameters.