Table 2.

Usefulness and pitfalls of diagnostic tools used in mycetoma

Diagnostic methods	Usefulness	Pitfalls
Clinical	Utilised in endemic areas where diagnostic facilities are lacking It boosts referral	Does not identify the etiologic agent Does not reveal the spread of disease along the different tissue planes and bone
Imaging
X-ray	Can determine the extent of lesions Multiple features can be detected Help plan treatment strategy Can be used in low-resource settings once expertise is available	Requires expert for interpretation
Ultrasound	Determine the extent of lesions Differentiate between mycetoma and non-mycetoma lesions Differentiate between eumycetoma and actinomycetoma Help plan appropriate treatment strategy Can be used in low-resource settings once expertise is available	Cannot differentiate between different causative agents Not readily available in the field or peripheral hospitals Requires expert for interpretation
MRI	Determine the extent of lesions Fast and non-invasive Help plan treatment strategy	Unsuitable for discrimination Available only in tertiary facilities Requires highly expert persons
CT	Determine the extent of lesions Discriminate eumycetoma between actinomycetoma It is fast and non-invasive Help plan appropriate treatment strategy	Not specific for early bony involvement Available only in tertiary facilities Requires highly expert persons
Laboratory
Microscopy	Cheaper and easy to use Can be utilised in the field and resource constraint settings Gram stain can distinguish fungal from bacteria agents Lacto-phenol cotton blue stain can differentiate fungal from bacterial filaments Acid fast stain helps identify the positive hyphae of Nocardia	Cannot identify specific etiologic agents
Culture	Gold standard for aetiology identification Aids in proper management of patients	Time consuming, contamination is common, high expertise needed Mostly available only in tertiary health care facilities
Histology/FNAC	Simple, rapid, sensitive and invasive but well tolerated by most patients Can distinguish eumycetoma from actinomycetoma	Requires expert to perform the procedure A pathologist is required to interpret the results General or regional anaesthesia needed Biopsy procedure requires experts
Serology	Less invasive procedure Cheaper and less time consumed Useful for measuring therapeutic response	Cannot reliably diagnose mycetomca Pure antigens needed Cross reactivity is a common challenge
Molecular-PCR	Fast, reliable and easy identification of causative agents Important for studying epidemiology of mycetoma agents Useful for generating accurate therapeutic data	Expensive, not readily available in endemic areas Only available in tertiary facilities Inappropriate for use in the field
Molecular-LAMP	Reliable identification of causative agents Can be used in resource-limited settings Relatively cheaper and easier compared to PCR User friendly	Less specific than PCR in identifying etiologic agents, possibility of field application

MRI magnetic resonance imaging, CT computed tomography, PCR polymerase chain reaction, FNAC fine needle aspiration cytology, LAMP loop-mediated isothermal amplification