Table 2 Usefulness and pitfalls of diagnostic tools used in mycetoma
From: Mycetoma: a clinical dilemma in resource limited settings
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 |