Thread by @BCMIDFellowship

Welcome to this week’s #IDFungiFriday #Tweetorial by @A_Spallonii 🍄

20yo AML➡️haploSCT➡️GI GVHD➡️relapse

Painful neck mass x2d + fever +sore throat +dysphagia +odynophagia

On exam, you feel a 3cm firm anterior neck mass. No erythema/fluctuance.

T38.1C, HR110, BP138/79, O2👍

What’s going on here?

#IDMedEd #IDTwitter #TxID @idfellows @IDSAMedEdCOP @AST_IDCOP @MarionHemmersb1 @DocWoc71 @TylerLambingMD @FungalDoc @DrFungus_MSGERC @FranciscoMarty_ @GermHunterMD @MSG_ERC @OncIDPharmd @EmilyBlumbergMD @RicardoLaHozMD @PergamIC @josh_nosanchuk @TxID_Edu

Answer:

All choices possible and should be considered in the DDx for a neck mass. Let’s get some imaging and labs on our pt and see what shakes out!

Algorithm for working up a neck mass in an adult 👇

CT shows:
🔸 low-attenuation lesion (3.7cm x 2.4 cm) in the R lobe thyroid gland.
🔸 numerous pulmonary nodules, concerning for invasive fungal pneumonia

Refresher on risk factors for fungal pneumonia 👇
tinyurl.com/yya7a5on

Some labs return…
🔸 WBC 0.1 K/uL
🔸 Baseline anemia, thrombocytopenia
🔸 Metabolic panel wnl

But the thyroid hormones…
🔸 TSH <0.01 mU/L (0.5-5.0)
🔸 FT4 2.5 ng/dl (0.7-1.9)
➡️ c/w hyperthyroid state

PET/CT showed hypermetabolic lesions of the R thyroid lobe:

Which is the most commonly reported cause of acute infectious thyroiditis?

Acute infectious thyroiditis with abscess formation can be from gram(+)or gram(-) organisms, which reach the thyroid either via hematogenous spread or contiguous spread/fistula.

Most common organisms involved in acute infectious thyroiditis are Staph > Strep > fungi!

FNA of pt’s thyroid mass yielded a diagnosis…
🔸 Fungal forms with hyphae + vascular invasion
🔸 Morphology most c/w Aspergillus (GMS, 60x)
🔸 Mold from culture identified as A. fumigatus

Fungal thyroiditis (FT) is rare… why?

Turns out, the thyroid gland is protected against microbes:
🔸 Rich blood supply
🔸 Good lymphatic drainage
🔸 Protective fibrous capsule
🔸 High glandular concentration of iodine may inhibit microbial growth

FT reported in all age groups (including neonates @BCMPedIDFellows)

More common in immunocompromised pts:
♦️ HIV/AIDS
♦️ Hematologic malignancies
♦️ Autoimmune dz, immunosuppressed
♦️ SOT/HSCT

(Preexisting thyroid disease not a predictor)

But FT is likely under-diagnosed/reported, esp in patients w/ disseminated fungal infections.

Autopsy-based study of 107 patients with invasive aspergillosis 👉 12% with thyroid involvement.

Clinical presentation:
💠 No symptoms
💠 Painful neck swelling
💠 Thyrotoxicosis

…but most will have evidence of ongoing disseminated fungal infection.

Biopsy may show fungal elements, focal abscess, hemorrhagic lesions surrounding blood vessels, diffuse necrosis.

In terms of micro… a variety of fungi have been implicated:
♦️ Aspergillus spp
♦️ Mucor
♦️ Candida spp
♦️ Cryptococcus neoformans
♦️ Coccidioides immitis
♦️ Histoplasma capsulatum
♦️ Pneumocystis jiroveci

Management:

Pathogen-directed antifungal therapy + source control.

In this case… pt was treated with L-AmB + voriconazole and a trip to IR.

But outcomes are poor d/t
🔸 Underlying condition (leukemia)
🔸 Late presentation/diagnosis

To recap:

🍄Infectious thyroiditis=bacteria>fungi
🍄Most common fungal cause = Aspergillus sp
🍄Seen mostly in immunocompromised hosts
🍄Can be asymptomatic ➡️ severe neck swelling/pain
🍄Tx Antifungal+debridement
🍄Mortality ⬆️ despite targeted antifungal therapy