Figure 1
Plain radiography of the right lower leg
Clinical History
Medical history of venous insufficiency of the lower legs presented with pain in the right foot and both lower limbs.
Imaging Findings
A HIV-positive patient with a medical history of venous insufficiency of the lower legs presented with pain in the right foot and both lower limbs.
On clinical examination there were purplebrown nodules on the skin of both feet, legs and arms. These nodules were histologically proven to be Kaposi-sarcoma. Conventional radiographs and MR-images of the lower legs and feet were obtained at that time. The patient received medication for both skin and bone lesions. MR-imaging was performed during and after therapy.
Plain radiography (fig. 1), AP view, of the right lower leg (A) shows multiple oval, sharply demarcated lytic lesions in the cortex of the tibia and fibula. Radiograph of the left calcaneus and midfoot, lateral view (B) demonstrates extensive osteolysis in the calcaneus and the midfoot. MR of the right foot (fig. 2), sagittal T2-weighted image (A) shows hyperintense lesions in the calcaneus and also in the midfoot. On coronal T1-weighted image of the tibia and fibula (B) before therapy there are multiple small nodular hypointense lesions in the bone marrow of both tibiae and proximal fibulae. On coronal T1-weighted image after therapy (C), the bone marrow lesions in the tibia have disappeared. Imaging findings in this HIV-positive man are caused by bacillary angiomatosis. The diagnosis was confirmed by a positive serology and good response to antibiotic therapy with erythromycin.
On clinical examination there were purplebrown nodules on the skin of both feet, legs and arms. These nodules were histologically proven to be Kaposi-sarcoma. Conventional radiographs and MR-images of the lower legs and feet were obtained at that time. The patient received medication for both skin and bone lesions. MR-imaging was performed during and after therapy.
Plain radiography (fig. 1), AP view, of the right lower leg (A) shows multiple oval, sharply demarcated lytic lesions in the cortex of the tibia and fibula. Radiograph of the left calcaneus and midfoot, lateral view (B) demonstrates extensive osteolysis in the calcaneus and the midfoot. MR of the right foot (fig. 2), sagittal T2-weighted image (A) shows hyperintense lesions in the calcaneus and also in the midfoot. On coronal T1-weighted image of the tibia and fibula (B) before therapy there are multiple small nodular hypointense lesions in the bone marrow of both tibiae and proximal fibulae. On coronal T1-weighted image after therapy (C), the bone marrow lesions in the tibia have disappeared. Imaging findings in this HIV-positive man are caused by bacillary angiomatosis. The diagnosis was confirmed by a positive serology and good response to antibiotic therapy with erythromycin.
Discussion
Bacillary angiomatosis is an infectious disease in immuno-compromized patients, caused by Bartonella henselae and Bartonella quintana. In immuno-competent patients, these microorganisms cause cat scratch disease. A few weeks after inoculation by a cat scratch or bite a regional lymphadenopathy develops usually in the elbow or axillary region.
Bacillary angiomatosis is characterized by a combination of highly vascular cutaneous and subcutaneous lesions, and osteolytic lesions. The cutaneous lesions are difficult to differentiate from Kaposi-sarcoma clinically and histopathologically. Histopathologically the Bartonella bactery can be found in the highly vascular cutaneous and subcutaneous nodules. The osseous lesions usually consist of well circumscribed lytic areas which occur in the medulla and/or cortex. The lesions have a high signal intensity on T2-weighted images and a low signal intensity on T1-weighted images. Less often there are ill defined regions of cortical destruction and medullary permeation with some periosteal reaction. Diagnosis is made with biopsy (Whartin-Starry stain or electromicroscopy) and serology. The presence of bone lesions can be detected on Tc-99m MPD-scintigraphy.
In case of involvement of the spleen and liver the disease is known as bacillary peliosis. The treatment consists of antibiotic therapy with erythromycin over a prolonged period resulting in regression and resolution of the osteolytic lesions.
Bacillary angiomatosis is characterized by a combination of highly vascular cutaneous and subcutaneous lesions, and osteolytic lesions. The cutaneous lesions are difficult to differentiate from Kaposi-sarcoma clinically and histopathologically. Histopathologically the Bartonella bactery can be found in the highly vascular cutaneous and subcutaneous nodules. The osseous lesions usually consist of well circumscribed lytic areas which occur in the medulla and/or cortex. The lesions have a high signal intensity on T2-weighted images and a low signal intensity on T1-weighted images. Less often there are ill defined regions of cortical destruction and medullary permeation with some periosteal reaction. Diagnosis is made with biopsy (Whartin-Starry stain or electromicroscopy) and serology. The presence of bone lesions can be detected on Tc-99m MPD-scintigraphy.
In case of involvement of the spleen and liver the disease is known as bacillary peliosis. The treatment consists of antibiotic therapy with erythromycin over a prolonged period resulting in regression and resolution of the osteolytic lesions.
Differential Diagnosis List
Bacillary angiomatosis
Final Diagnosis
Bacillary angiomatosis
References
[1] Baron A.L., Steinbach L.S., LeBoit P.E., et al.: Osteolytic lesions and bacillary angiomatosis in HIV infection: radiologic differentiation from AIDS-related Kaposi sarcoma. Radiology, 1990, 177: 77-81. (PMID: 2399342)
[2] Dong P.R., Seeger L.L., Yao L., et al.: Uncomplicated cat-scratch disease: findings at CT, MR imaging, and radiography. Radiology, 1995, 195: 837-839. (PMID: 7754017)
[3] Herts B.R., Rafii M., Spiegel G.: Soft-tissue and osseous lesions caused by bacillary angiomatosis: unusual manifestations of cat-scratch fever in patients with AIDS. AJR, 1991, 157: 1249-1251. (PMID: 1950875)
[4] Jeurissen A., Verhaegen J.: Bartonella-infecties: van kattenkrabziekte tot bacillaire angiomatosepeliose. Tijdschr Geneesk, 1999, 55: 255-260.
Case information
| URL: | https://www.eurorad.org/case/1717 |
| DOI: | 10.1594/EURORAD/CASE.1717 |
| ISSN: | 1563-4086 |
Figure 2
The left calcaneus and midfoot, MRI studies
MR of the right foot, sagittal T2-weighted image shows hyperintense lesions in the calcaneus and also in the midfoot.
On coronal T1-weighted image of the tibia and fibula before therapy there are multiple small nodular hypointense lesions in the bone marrow of both tibiae and proximal fibulae.
On coronal T1-weighted image after therapy. MRI of the tibia and fibula, the bone marrow lesions in the tibia have disappeared.
Plain radiography of the right lower leg
The left calcaneus and midfoot, MRI studies
MR of the right foot, sagittal T2-weighted image shows hyperintense lesions in the calcaneus and also in the midfoot.
On coronal T1-weighted image of the tibia and fibula before therapy there are multiple small nodular hypointense lesions in the bone marrow of both tibiae and proximal fibulae.
On coronal T1-weighted image after therapy. MRI of the tibia and fibula, the bone marrow lesions in the tibia have disappeared.