Disseminated cryptococcosis with recurrent multiple abscesses in an immunocompetent patient: a case report and literature review

Abstract

Background: Cryptococcus neoformans is frequently present as an opportunistic pathogen mainly affecting immunocompromised populations. Disseminated C. neoformans infection in immunocompetent population is rare and usually involves lung and central nerve system. Cryptococcus from biologic samples can easily grow on routine fungal and bacterial culture media. Besides, cryptococcal latex agglutination test has been established as a reliable diagnostic tool with overall sensitivities of 93-100%.

Case presentation: We report a rare disseminated cryptococcosis case which presented with chronic recurrent multiple abscess in an immunocompetent male involving skin, lung, spine and iliac fossa without evidence of central nerve system involving. The results of serum cryptococcal latex agglutination tests and standard microbial cultures were negative. The patient underwent empirical anti-bacterial and anti-tuberculosis therapy which turned out to be effectless. Finally, bedside inoculation of the pus was carried out and revealed Cryptococcus neoformans, which was confirmed by polymerase chain reaction. After the administration of anti-fungal drugs including liposomal amphotericin B, the patient recovered from fever and paraplegia.

Conclusions: This case reveals an uncommon pattern of disseminated C. neoformans infection in immunocompetent population presented with chronic multiple abscess and without central nerve system involving. Negative routine microbial cultures may not necessarily rule out cryptococcosis, especially in early stage. Besides, cryptococcal latex agglutination test does have a chance of false negative, which might be related with "capsule-deficiency". Moreover, this phenomenon could be related with low-grade virulence and relative long illness duration.

Keywords: Abscess; Cryptococcosis; Immunocompetent.

Fig. 1

The lump on the back: There was a bean-size lump with slight tenderness on the left side of the lower back

Fig. 2

Abscess in lung and fascia: Chest CT scan revealed pulmonary abscess formation (above) and an abscess inside the fascia (below)

Fig. 3

CT scan revealed progressing infection: Chest CT scan revealed the unresolved pulmonary abscess (above) compared with 2 months before (Fig. 2). Moreover, there were additional multiple destructions of vertebral bodies, especially T5 in the figure below

Fig. 4

Bone destructions and compressed spine: These two sagittal views of spinal MRI T2-weighted sequence revealed multiple bone destructions of thoracic vertebrae, with spine compressed at T4 and T5 level

Fig. 5

Contrasted CT scan and non-contrasted MRI scan of pelvic cavity: a Axial view of CT scan. b Coronal view of CT scan. c Coronal view of MRI T1-weighted fast spin echo sequence. d Coronal view of MRI short TI inversion recovery sequence. Both CT and MRI scan revealed a large right iliac abscess

Fig. 6

India ink staining of the pus culture: The cryptococcus can be found in the pus culture after the India ink staining

Fig. 7

Gantt chart: The Gantt chart illustrates the course of the patient’s disease