TRansplant patient . - guest78

[ArchivalUser]

A 28-year-old man who underwent stem-cell transplantation 8 months ago is evaluated because of a persistent cough and possible fever. Until now, he had been doing well and had recently returned to work. Current medications are cyclosporine, sirolimus, and prednisone.

On physical examination, he has a Hickman catheter in place that has not been used for more than 1 month. General examination, including temperature and arterial oxygen saturation, is normal. A chest radiograph shows a single new 2.5-cm nodule in the right mid-lung. An immediate serum cryptococcal antigen assay is negative.

In addition to obtaining blood and sputum cultures, which of the following is most appropriate at this time?

A Remove the Hickman catheter
B Obtain a CT scan of the chest
C Begin voriconazole
D Obtain a galactomannan assay
E No therapy or diagnostic studies are indicated; repeat the chest radiograph in 2 weeks

[ArchivalUser]

a..?

[ArchivalUser]

B. new findng of nodule on CXR warrants another diagnostic test.

[ArchivalUser]

aaa. and then take peripheral culture from the catheter

[ArchivalUser]

AAAA

[ArchivalUser]

C

[ArchivalUser]

B..

[ArchivalUser]

answer is BBB.

This patient has a clinically mild but potentially important pulmonary process. Although diffuse involvement is possible, the disease currently appears to be confined to a small area in the right lung. A CT scan of the chest may provide additional information about possible causes (e.g., a œhalo sign indicative of Aspergillus or some other mold), but, most importantly, a scan may identify other lesions (e.g., from septic emboli arising from the catheter) or allow radiographic-guided needle biopsy of any lesions that are identified.

Removing the Hickman catheter is appropriate if the nodule is due to an embolism or is associated with an infection, but a CT scan and blood and sputum cultures should be obtained first. In addition, the catheter may soon be needed for intravenous access. Voriconazole should be started only if a fungal infection such as Aspergillus, Scedosporium, Cryptococcus, or Candida is diagnosed. However, voriconazole has significant drug interactions with sirolimus and should not be used unless sirolimus therapy can be very closely monitored or stopped. Galactomannan assays are not indicated because they are not widely available, are not sensitive enough to identify Aspergillus without the need for confirmation with cultures, and cannot detect other fungi, including molds that may resemble Aspergillus clinically. Delaying therapy for 2 weeks may or may not be harmful, depending on the diagnosis. However, the patient already has a cough and may have a disease that requires immediate treatment once the CT scan results are obtained.