Title: Severe Disseminated Coccidioidomycosis in a Filipino Immunocompetent Woman
Submitted by: Leah M. Friedman1, Karolina D. Perez2, Rachel L. Wu2, Mehraneh Mohseni Zadeh Harouzi2, Fariba M. Donovan3,4
Institution:
1A.T. Still University – School of Osteopathic Medicine in Arizona
2University of Arizona, Tucson, Arizona, USA
3Valley Fever Center for Excellence, College of Medicine-Tucson, University of Arizona, Arizona, USA
4Division of Infectious Diseases, College of Medicine-Tucson, University of Arizona, Arizona, USA
Email: leah.friedman@atsu.edu
Date Submitted:12/18/25
History:
A 35-year-old Filipino woman with an unremarkable past medical history, originally from Seattle, WA and residing in Tucson, Arizona since 2013, developed flu-like symptoms, including cough, fever, chills, night sweats, and malaise in November 2024. She was initially treated with a short course of antibiotics and prednisone at an urgent care clinic, with minimal improvement.
In April 2025, she developed a palpable left supraclavicular lymph node and underwent biopsy to rule out malignancy. The biopsy was negative for lymphoma, and she was treated with antibiotics for presumed cellulitis without improvement.
Subsequent Coccidioides serology confirmed coccidioidomycosis, and she was started on fluconazole 400 mg daily, with initial symptomatic improvement. Subsequently, she was switched to posaconazole.
By May 2025, she developed purulent drainage from the supraclavicular lymph nodes. A repeat biopsy demonstrated granulomatous inflammation with spherules consistent with disseminated coccidioidomycosis. She later developed progressive lymphadenopathy involving the right supraclavicular and submental regions with recurrent drainage. Over the next several months, she experienced persistent weight loss (from 99 to 89 Ibs) and back pain, prompting imaging that confirmed osseous dissemination.
At her most recent follow-up, the patient reported a sensation of ear fullness, raising concern for possible coccidioidal meningitis. She underwent brain MRI and lumbar puncture, both of which were negative for Coccidioides meningitis. She continues a close follow-up with the Valley Fever Clinic at the University of Arizona.
Physical Examination:
Skin: The patient had persisting bilateral supraclavicular wounds that were well-crusted, as well as submandibular and submental lymphadenopathy with overlying crusted lesions. Otherwise, the skin was warm, dry, and pink, with no rashes or additional lesions.
Laboratory Examination:
Serum:
– CF titer: 1:256
– Fluconazole level: 25.1 µg/mL
– Posaconazole level: 2.92 µg/mL
– Coccidioides EIA IgG/IgM: None detected
CSF:
– Coccidioidal CF: Negative
– MVista® Coccidioides antigen quantitative EIA: None detected
Question 1: What are probable/possible diagnoses?
Microbiology and Diagnostic Testing:
Diagnostic evaluation included biopsy, CT chest, MRI abdomen, MRI spine, brain MRI, and lumbar puncture.
CT Chest:
Imaging demonstrated diffuse miliary nodules with a stable overall appearance of the chest and a prominent 6 mm nodule in the left upper lobe. Additionally, mediastinal and hilar adenopathy was noted.
MRI Abdomen:
The spleen demonstrated a markedly heterogeneous appearance with multiple lesions. There was a 2.5 cm enlarged inferior thoracic lymph node and 1.4 cm paraspinal nodule along T11 vertebrae.
MRI Spine:
An incidental T11 spinal lesion was identified involving the left posterolateral vertebral body and extending into the pedicle, consistent with osseous dissemination of coccidioidomycosis.
Brain MRI:
Brain MRI demonstrated a small focus of leptomeningeal enhancement in the right parieto-occipital sulcus, raising concern for possible early meningitis involvement.
Final Diagnosis: Disseminated coccidioidomycosis with lymphatic, osseous, and splenic involvement.
Question 2: What treatment is recommended in the care of this patient?
Treatment:
The patient initially received fluconazole 400 mg daily. Subsequently, she was switched to posaconazole due to minimal improvement on fluconazole. However, she developed posaconazole side effects and was switched back to fluconazole which is currently ongoing.
Outcome:
The patient remains clinically stable on fluconazole 400 mg daily. She continues with regular follow up visits.
Discussion: (500 words)
Coccidioidomycosis, also known as Valley fever, is a fungal infection that is endemic to the Southwestern United States. Disease severity ranges from asymptomatic infection to severe pulmonary disease and disseminated coccidioidomycosis. ¹ Although immunosuppression is a recognized risk factor for dissemination, host-related factors such as genetic predisposition and ethnic background also significantly influence disease severity. Individuals of African American and Filipino ancestry are at increased risk for dissemination. ² One study reported that individuals of Filipino ethnicity may have up to a one hundred seventy-five-fold higher risk of developing disseminated coccidioidomycosis compared with Caucasian patients. ²
Although all residents of endemic regions are at risk for coccidioidomycosis, certain populations, including those of Filipino descent, experience a disproportionately higher rate of dissemination. The causes of these disparities remain uncertain. Genetic factors such as blood group type and HLA alleles, including HLA DRB1*1301, have been associated with more severe disease. These markers may represent indirect indicators of host susceptibility rather than direct causal mechanisms. ³
This case describes an immunocompetent Filipino woman with no comorbidities or history of immunosuppression who developed disseminated coccidioidomycosis. Despite an intact immune system and ongoing antifungal therapy, she developed widespread dissemination involving the lymphatic system, osseous structures, and spleen.
Treatment was complicated by intolerance to antifungal medication. The patient was transitioned from fluconazole to posaconazole for better response to treatment. However, she developed posaconazole related side effects such as facial swelling, increased cough, and weight gain, which required discontinuation. This reflects a common challenge in the management of coccidioidomycosis, where achieving adequate antifungal exposure must be balanced with medication tolerability. Even with multiple azole options available, progressive or recurrent disease remains a significant concern in high-risk populations. ⁴
In the fall of 2025, a brain MRI demonstrated focal leptomeningeal enhancement, raising concern for Coccidioides meningitis. Cerebrospinal fluid analysis was negative for Coccidioides antigen and complement fixation by multiple methods, including MVista Coccidioides Antigen Quantitative EIA. ⁵ These findings confirmed absence of central nervous system involvement at that time.
This case emphasizes several key clinical principles. Ethnicity should be incorporated into risk assessment for patients with suspected or confirmed coccidioidomycosis. Persistent or progressive disease despite antifungal therapy should prompt evaluation of drug absorption, serum levels, medication tolerance, and possible resistance. Clinicians practicing in endemic regions should maintain a high index of suspicion for disseminated disease in Filipino and African American patients, even when no immunocompromising conditions are present. Early recognition and timely intervention remain essential to improving patient outcomes.
In summary, disseminated coccidioidomycosis can occur in immunocompetent individuals, particularly among those of certain ethnicity. This case illustrates the importance of considering genetic and ethnic susceptibility when evaluating, managing, and preventing severe forms of coccidioidomycosis.
Key References:
- Donovan FM, Fernández OM, Bains G, Di Pompo L. Coccidioidomycosis: a growing global concern. Journal of Antimicrobial Chemotherapy. 2025;80(Supplement_1): i40-i49. doi:10.1093/jac/dkaf002
- Hsu AP. The Known and Unknown “Knowns” of Human Susceptibility to Coccidioidomycosis. Journal of Fungi. 2024;10(4):256.
- Vinh DC, Masannat F, Dzioba RB, Galgiani JN, Holland SM. Refractory disseminated coccidioidomycosis and mycobacteriosis in interferon-gamma receptor 1 deficiency. Clin Infect Dis. Sep 15, 2009;49(6): e62-5. doi:10.1086/605532
- Crum, N.F. Coccidioidomycosis: A Contemporary Review. Infect Dis Ther 11, 713–742 (2022). https://doi.org/10.1007/s40121-022-00606-y
- Christelle Kassis, Syed Zaidi, Timothy Kuberski, Ana Moran, Omar Gonzalez, Sana Hussain, Carlos Hartmann-Manrique, Layth Al-Jashaami, Ahmad Chebbo, Robert Andy Myers, Laurence Joseph Wheat, Role of Coccidioides Antigen Testing in the Cerebrospinal Fluid for the Diagnosis of Coccidioidal Meningitis, Clinical Infectious Diseases, Volume 61, Issue 10, 15 November 2015, Pages 1521–1526, https://doi.org/10.1093/cid/civ585