Molecular diagnosis of infectious diseases using cytological specimens

Abstract

Pathologists have an important role in the diagnosis of infectious disease (ID). In many cases, a definitive diagnosis can be made using cytopathology alone. However, several ancillary techniques can be used on cytological material to reach a specific diagnosis by identifying the causative agent and consequently defining the management of the patient. This review aims to present the effectiveness of the application of molecular studies on cytological material to diagnose IDs and discuss the advantages and disadvantages of the various molecular techniques according to the type of cytological specimen and the infectious agents.

Lung cancer samples preserved in liquid medium: One step beyond cytology

“…82 The diagnosis of microorganisms is based particularly on molecular methods of nucleic acid analysis and microarrays, and classified as amplified, unamplified. 83 In clinical practice, PCR is the most common method for the detection of microorganisms such as Streptococcus pneumonia, Mycoplasma pneumonia and Staphylococcus aureus, among others. Currently, real-time PCR has been widely used because it offers a lower risk of contamination, rapid turn-around and its sensitivity allows the detection of infectious agents found in low concentrations in cytological samples.…”

“…Because the lung is the largest epithelial surface in the body, it constitutes the major portal for the entry of microorganisms such as viruses, bacteria and fungal organisms . The diagnosis of microorganisms is based particularly on molecular methods of nucleic acid analysis and microarrays, and classified as amplified, unamplified . In clinical practice, PCR is the most common method for the detection of microorganisms such as Streptococcus pneumonia , Mycoplasma pneumonia and Staphylococcus aureus , among others.…”

Identification of infectious organisms in cytopathology: A review of ancillary diagnostic techniques

“…For example, induced sputum and voided urine specimens are easy to collect; however, both specimens are limited by high rates of contamination with oral and genital flora, respectively, and typically do not provide enough material for special and immunostaining ancillary techniques . Advances in molecular diagnostics, such as human papillomavirus (HPV) testing on liquid‐based, cervical Papanicolaou (Pap) specimens, though, have led to an increasing menu of diagnostic tests available for microorganism identification on cytology specimens . Conversely, FNA of superficial or deep lesions may be more technically challenging to obtain; however, sampling can be directly targeted and ample material may be obtained for a wide variety of ancillary studies.…”

“…1,2 Advances in molecular diagnostics, such as human papillomavirus (HPV) testing Cancer Cytopathology August 2018 on liquid-based, cervical Papanicolaou (Pap) specimens, though, have led to an increasing menu of diagnostic tests available for microorganism identification on cytology specimens. 3 Conversely, FNA of superficial or deep lesions may be more technically challenging to obtain; however, sampling can be directly targeted and ample material may be obtained for a wide variety of ancillary studies. Routine cytology stains, including the Pap and the Diff-Quik stains, can adequately identify a number of microorganisms (Table 2).…”

Molecular diagnostic techniques in cytopathology: From the bench to the patient's bedside

“…However, cytological samples are heterogeneous and no standardized processing protocols have been published . The implementation of new immunocytochemical and molecular markers is not only a valuable resource for patient management and prognosis, but also a tool to study metastatic tumors of unknown origin or infectious diseases . It seems clear that the “do more with less” policy is becoming increasingly important and the optimization of cytological material is essential .…”