Discussion
Diagnosis With Brief Discussion
- Diagnosis
- Multifocal micronodular pneumocyte hyperplasia (MMPH) in tuberous sclerosis
- Radiologic Findings
- Fig 1. Chest PA shows bilateral diffuse fine nodular opacities.
Fig 2-3. Chest CT images demonstrate multiple nodules, varying in diameter from 1 to 5mm, with a diffuse and random distribution in both lungs.
Fig 4-5. CT images with a bone window setting reveal multifocal osteosclerotic lesions involving thoracic spines.
- Brief Review
- MMPH is a manifestation of tuberous sclerosis complex (TSC) in both female and male patients. It is a hamartomatous process of the lung that exhibits multiple tiny pulmonary nodules. Pathologically, it is characterized by the proliferation of type II pneumocystis along the alveolar septa.
Radiologically, MMPH presents as multiple nodules on CT. Nodules are 1-8mm in diameter and are diffusely scattered throughout the lung in a random distribution with regard to the secondary pulmonary lobule.
The differential diagnosis should also include a miliary granulomatous infection, Langerhans’ cell histiocytosis, hematogenous metastasis and multiple atypical adenomatous hyperplasia/adenocarcinoma in situ. The presence of multiple tiny pulmonary nodules in a random distribution in a TSC patient should suggest the presence of MMPH.
The clinical manifestations resulting from isolated MMPH are dyspnea, cough, and mild to moderate hypoxemia. The clinical course of MMPH is usually not progressive and treatment is unnecessary.
- Please refer to
Case 543, Case 979, -
KSTR imaging conference 2018 Spring Case 15,
- References
- 1. Ristagno R-L, Biddinger P-W, Pina E-M, Meyer C-A. Multifocal micronodular pneumocyte hyperplasia in Tuberous Sclerosis. AJR 2005;184-37-39
2. Lee I-S, Shim H-S, Lee H-J, Kang Y-A. Multifocal micronodular pneumocyte hyperplasia mimicking military tuberculosis. Am J Respir Crit care Med 2014;189:225-226
3. Pannu B-S, Apala D-R, Kotecha A, Boland J-M, Iyer V-N. Multifocal micronodular pneumocyte hyperplasia (MMPH) in a patient with tuberous sclerosis-evidence for long term stability. Respiratory Medicine Case Reports 2017; 20:113-115
- Keywords
- MMPH, Tuberous sclerosis, lung, bone,