NOS2-derived nitric oxide regulates the size, quantity and quality of granuloma formation in Mycobacterium avium-infected mice without affecting bacterial loads.
Granuloma formation in response to mycobacterial infections is associated with increased expression of inducible nitric oxide synthase (NOS2) within granuloma macrophages and increased levels of nitrate/nitrite in the sera of infected mice. Continuous treatment with 5 mm or 10 mm l-N6-(1-imino-ethyl)-lysine (L-NIL), a selective NOS2-inhibitor, in acidified drinking water for up to 7 weeks consistently reduced infection-induced nitrate/nitrite to background levels in mycobacteria-infected BALB/c mice. Oral treatment with 5 mm L-NIL initiated at the time of infection significantly exacerbated growth of Mycobacterium tuberculosis, but had no effect on Mycobacterium avium colony-forming unit development in the liver, spleen and lungs of intravenously infected mice. In order to examine the role of nitric oxide in mycobacteria-induced granulomatous inflammation in the absence of any effect on the bacterial load, M. avium-infected mice were treated with 5 mm L-NIL from day 1 through 38 and the development of granulomatous lesions in the liver was assessed by histology, immunohistology and reverse-transcription-polymerase chain reaction (RT-PCR). Computer- and video-assisted morphometry performed at 4 and 7 weeks post-infection showed that treatment with L-NIL led to markedly increased number, cellularity and size of granulomatous lesions in infected mice regardless of the virulence of the M. avium isolate used for infection. Immunohistology of the liver revealed that in mice treated with L-NIL, the numbers of CD3+ T cells, CD21/35+ B cells, CD11b+ macrophages and RB6-8C5+ granulocytes associated with granulomatous lesions was increased. RT-PCR of the liver showed that in L-NIL-treated mice infected with M. avium, mRNA levels of tumour necrosis factor, interleukin-12p40, interferon-gamma, interleukin-10 and interferon-gamma-inducible protein-10 (IP-10) were up-regulated, while mRNA levels of interleukin-4, monocyte chemotactic protein-1 (MCP-1) and MCP-5 were similar to those in untreated control infected mice. When M. avium-infected mice were treated with 5 mm L-NIL between the 5th and 12th weeks of infection, similar changes in granuloma number and size were found in the absence of any effect on the bacterial load. These findings demonstrate that nitric oxide regulates the number, size and cellular composition of M. avium-induced granulomas independently of antibacterial effects by modulating the cytokine profile within infected tissues. (+info)
Isolated tuberculous hepatic abscess in a non-immunocompromised patient.
A 38 years old female presented with pain in the epigastrium, jaundice and fever since one and half month. The computerised tomographic scan of the abdomen revealed a multiloculated abscess of the left lobe of liver. The pus drained from the liver abscess at laparotomy showed acid fast bacilli on microscopy. A detailed search failed to identify any other focus of tuberculous infection. The case has been reported for the rarity of isolated hepatic tuberculous abscess and its presentation with jaundice, a rare feature, and to highlight the importance of microscopic or culture diagnosis in a suspected case of pyaemic abscess. (+info)
Primary solitary tuberculosis of the liver.
Primary solitary tuberculous involvement of the liver is a rare condition. We present the case of a patient who was operated on with a preoperative diagnosis of hepatocellular carcinoma. Liver resection was performed and antituberculous therapy was started. It is difficult to make the correct diagnosis preoperatively except when a successful needle biopsy can be performed. Despite the rarity of the condition primary solitary tuberculosis should be considered among the space occupying lesions of the liver. (+info)
The nodular form of hepatic tuberculosis: a review with five additional new cases.
BACKGROUND: Tuberculosis presenting as an isolated liver tumour, without active pulmonary or miliary tuberculosis, or other clinical evidence of tuberculosis, is distinctly rare. A greater awareness of this rare clinical entity may prevent needless surgical intervention. AIMS: To help characterise this distinctly rare presentation of tuberculosis, five new cases are presented, together with a review of the world literature. The clinical, laboratory, radiological, and pathological features of these patients are described. METHODS: Polymerase chain reaction (PCR) assay of the liver tissue was carried out in all cases to confirm an aetiological diagnosis of Mycobacterium tuberculosis infection. RESULTS: All five patients (44-71 years old; two women, three men) underwent surgery, and had a preoperative diagnosis of malignant hepatic neoplasm and a postoperative histological diagnosis of chronic granulomatous inflammation, suggestive of tuberculosis. None of them had a known previous history of tuberculosis. All of them were positive for M tuberculosis by PCR analysis of the liver tissue. CONCLUSIONS: This report illustrates the difficulty in reaching a correct preoperative diagnosis. It is usually unsuspected and confused with primary or metastatic carcinoma of the liver, especially when it coexists with other malignancies. A high index of suspicion is required for diagnosis, which can be made only by histological and bacteriological studies, and PCR analysis. (+info)
Imaging diagnosis of 12 patients with hepatic tuberculosis.
AIM: To assess CT, MR manifestations and their diagnostic value in hepatic tuberculosis. METHODS: CT findings in 12 cases and MR findings in 4 cases of hepatic tuberculosis proved by surgery or biopsy were retrospectively analyzed. RESULTS: (1) CT findings: One case of serohepatic type of hepatic tuberculosis had multiple-nodular lesions in the subcapsule of liver. Parenchymal type was found in 10 cases, including multiple, miliary, micronodular and low-density lesions with miliary calcifications in 2 cases; singular, low-density mass with multiple flecked calcifications in 3 cases; multiple cystic lesions in 1 case; multiple micronodular and low-density lesions fusing into multiloculated cystic mass or "cluster" sign in 3 cases; and singular, macronodular and low-density lesion with multiple miliary calcifications in 1 case. One case of tuberculous cholangitis showed marked dilated intrahepatic ducts with multiple flecked calcifications in the porta hepatis. (2) MR findings in 4 cases were hypointense on both T1-weighted imagings and T2-weighted imagings in one case, hypointense on T1-weighted imagings and hyperintense on T2-weighted imagings in 3 cases. Enhanced MR in 3 cases was slightly shown peripheral enhancement or with multilocular enhancement. CONCLUSION: Various types of hepatic tuberculosis have different imaging findings, and typical CT and MR findings can suggest the diagnosis. (+info)
Tuberculous liver abscess not associated with lung involvement.
Hepatic tuberculosis is one of the uncommon forms of extrapulmonary tuberculosis. We report a 78-year-old woman who developed tuberculous liver abscesses with splenic abscess not associated with pulmonary foci. Ultrasonography and computed tomography of the abdomen showed the low-density lesions in the liver and spleen. Histopathology of specimens obtained by percutaneous needle biopsy revealed coagulation necrosis and epithelioid cells but not tumor cells, suggesting tuberculosis infection in the liver and spleen. Systemic chemotherapy with anti-tuberculous agents led to the improvement of the lesions in the liver as well as spleen. Although tuberculous liver abscess is a very rare case, it should be included in the differential diagnosis of unknown hepatic mass lesions. (+info)
Hypercalcemia in hepatic tuberculosis: a case report in Korea.
Although primary hyperparathyroidism and malignant diseases account for approximately 90% of the causes of hypercalcemia, they could occur in association with granulomatous diseases such as tuberculosis or sarcoidosis, especially in developing countries. Hepatic tuberculosis is difficult to diagnosis without suspicion in cases with normal findings on chest radiographs. We report a 70-year-old woman who presented with hypercalcemia due to hepatic tuberculosis. The diagnosis was made by a computed tomography scan and laparoscopic evaluation. After treatment with anti-tuberculosis medication, her hypercalcemia resolved. Increased vitamin D synthesis by activated macrophages in the granuloma tissue is the major mechanism of hypercalcemia in tuberculosis. (+info)
Hepatic segmentectomy for treatment of hepatic tuberculous pseudotumor.
BACKGROUND: This study was designed to explore the preoperative diagnosis and surgical modality of patients with hepatic tuberculous pseudotumor. METHODS: Of 682 patients who had undergone liver resection from January 1988 to December 2004, 8 were confirmed pathologically as having hepatic tuberculous pseudotumor after operation. Their clinical features, laboratory findings,results of preoperative imaging and surgical modality of the 8 patients were analyzed. RESULTS: In these patients, 5 were misinterpreted as having other types of liver tumor and 3 were confirmed as having liver tuberculous pseudotumor preoperatively. All the 8 patients underwent hepatic segmentectomy and local hepatic resection. Seven had no tumor recurrence after follow-up for 4 years. CONCLUSIONS: Hepatic tuberculous pseudotumor was highly suspected for the patients with hepatic occupying-space lesions who had a history of tuberculosis. Fine needle aspiration liver biopsy guided by B-mode ultrasound and CT scan could confirm the diagnosis. They are of vital importance in the pathological diagnosis of the tumor. Therapeutic modalities included all kinds of hepatic segmentectomy and postoperative administration of antituberculous agents for the enhancement of the therapeutic effects. (+info)