Invasive aspergillosis in liver transplant recipients, an infectious complication with low incidence but significant mortality

BACKGROUND

Infections, including invasive fungal infections (IFIs), are among the leading causes of mortality in liver transplant recipients during the first year post-transplantation.

AIM

To investigate the epidemiology, clinical manifestations, risk factors, treatment outcomes, and mortality rate of post-liver transplantation invasive aspergillosis (IA).

METHODS

In this case-control study, 22 patients with IA were identified by reviewing the archived and electronic medical records of 850 patients who received liver transplants at the Imam Khomeini Hospital complex in Tehran, Iran, between 2014 and 2019. The control group comprised 38 patients without IA infection matched for age and sex. The information obtained included the baseline characteristics of liver transplant patients, operative reports, post-transplantation characteristics of both groups and information about the fungal infection of the patient group.

RESULTS

The prevalence rate of IA among liver transplant recipients at Imam Khomeini Hospital was 2.7%. The risk factors of IA among studied patients included high serum creatinine levels before and post-transplant, renal replacement therapy, antithymocyte globulin induction therapy, post-transplant bile leakage, post-transplant hepatic artery thrombosis, repeated surgery within 30 d after the transplant, bacterial pneumonia before the aspergillosis diagnosis, receiving systemic antibiotics before the aspergillus infection, cytomegalovirus infection, and duration of post-transplant hospitalization in the intensive care unit. The most prevalent form of infection was invasive pulmonary aspergillosis, and the most common chest computed tomography scan findings were nodules, pleural effusion, and the halo sign. In the case group, prophylactic antifungal therapy was administered more frequently than in the control group. The antifungal therapy response rate at 12 wk was 63.7%. The 3- and 12- mo mortality rates of the patients with IA were 36.4% and 45.4%, respectively (compared with the mortality rate of the control group in 12 mo, which was zero).

CONCLUSION

In this study, the prevalence of IA among liver transplant recipients was relatively low. However, it was one of the leading causes of mortality following liver transplantation. Targeted antifungal therapy may be a factor in the low incidence of infections at our facility. Identifying the risk factors of IFIs, maintaining an elevated level of clinical suspicion, and initiating early antifungal treatment may significantly improve the prognosis and reduce the mortality rate of liver transplant recipients.

Statin Use May Be Associated With a Lower Risk of Invasive Aspergillosis in Lung Transplant Recipients

BACKGROUND

Statins are competitive inhibitors of 3-hydroxy-3methylglutaryl coenzyme A reductase (HMG-CoA reductase) that catalyses HMG-CoA conversion to mevalonate, a process involved in synthesizing cholesterol in humans and ergosterol in fungi. The effect of statin use on the risk of development of invasive aspergillosis (IA) in lung transplant recipients (LTRs) is not well documented.

METHODS

This retrospective study included LTRs from 2010 to 2017 who were followed for one-year post-transplant. Proven or probable IA was diagnosed as per ISHLT criteria. We performed a multivariable Cox proportional hazards model of the association between IA and statin use (minimum of 2 weeks duration prior to IA), adjusting for other known IA risk factors.

RESULTS

We identified 785 LTRs, 44% female, mean age 53 years old, the most common underlying disease being pulmonary fibrosis (23.8%). In total, 451 LTRs (57%) received statins post-transplant, atorvastatin was the most commonly used statin (68%). The mean duration of statins post-transplant was 347 days (interquartile range [IQR]: 305 to 346). And 55 (7%) LTRs developed IA in the first-year post-transplant. Out of these 55 LTRs, 9 (16.3%) had received statin before developing IA. In multivariable analysis, statin use was independently associated with a lower risk of IA (P = .002, SHR 0.30, 95% confidence interval [CI] 95% .14-.64). Statin use was also associated with a lower incidence of post-transplant Aspergillus colonization, 114 (34%) in the no statin group vs 123 (27%) in the statin group (P = .038).

CONCLUSIONS

The use of statin for a minimum of two weeks during the first-year post-transplant was associated with a 70% risk reduction of IA in LTRs.

Antifungal prophylaxis in adult lung transplant recipients: Uncertainty despite 30 years of experience. A systematic review of the literature and network meta-analysis

BACKGROUND

Invasive fungal infections (IFI), particularly invasive aspergillosis (IA), cause significant morbidity and mortality in lung transplant (LTx) recipients. The optimum strategy and antifungal agents for prevention are unclear.

METHODS

We performed a comprehensive literature search, systematic review, and network meta-analysis using a frequentist framework to compare the efficacy of various antifungal drugs on the incidence of IA/IFI in the setting of universal prophylaxis or no prophylaxis following lung transplantation.

RESULTS

We included 13 eligible studies comprising of 1515 LTx recipients and 12 different prophylaxis strategies/antifungal combinations. The greatest number of direct comparisons were between the inhaled amphotericin formulations. The top three ranked treatments were inhaled liposomal amphotericin B (L-AmB), inhaled amphotericin deoxycholate (AmBd), and itraconazole plus inhaled amphotericin B (AmB). Among the azoles, isavuconazole ranked highest. The certainty of the evidence, assessed using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) framework, was very low.

CONCLUSION

Although universal antifungal prophylaxis post lung transplantation is commonly used, robust data from randomized controlled trials (RCTs) to inform the choice of antifungal agent and prophylaxis strategy are lacking. This exploratory network meta-analysis provides insight into the probable relative effectiveness of various antifungal agents in preventing IA, and this analysis should serve as a guide when selecting antifungals to be assessed in a RCT.

City Challenge: Sustainable Process or Temporary Gesture?

In this paper, the processes of governance within the UK government's recent urban policy initiative, City Challenge, are explored. This initiative targets the involvement, through “partnership”, of residents of “areas of concentrated disadvantage” in the processes of programme formulation and delivery. Underlying this is the objective of “incorporating” neighourhood residents in ‘mainstream’ political and economic life. In this paper, that objective is set in the context of contemporary conditions in such neighbourhoods. Experiences of the early stages of two City Challenge programmes are then discussed, in order to assess the character of the partnerships which are evolving. The two examples vary significantly in their style and in the strategy of the local authority, as well as in the characteristics of the areas. It is argued that, although central government's influence over the style of the programmes remains pervasive, the strategy of the local authority and the struggles by the participants in the partnerships have a significant influence on the content and style of the programmes. Further, the style of the programmes affects the balance of power within the programme and the terms of incorporation of the various partnerships in governance processes.

Inferior Epigastric Artery Pseudoaneurysm Following Paracentesis in a Liver Graft Recipient: A Case Report

Pseudoaneurysm happens when the artery wall is injured and the blood is contained by the surrounding tissues with eventual formation of a fibrous sac communicating with the artery. We report a case of a 39-year-old man with inferior epigastric artery (IEA) pseudoaneurysm after paracentesis. The pseudoaneurysm was diagnosed by Doppler ultrasound and treated by surgical intervention regarding the patient’s underlying comorbidity. IEA false aneurysm must be included in the differential diagnosis during investigation of the cause of any swelling after paracentesis. Cirrhotic patients may be more prone to this complication because of thin rectus muscle that could not confine the hematoma.

Invasive mould sinusitis in patients with haematological malignancies: a 10 year single-centre study

OBJECTIVES

Invasive mould sinusitis (IMS) is a severe infection in patients with haematological malignancies. Because of a paucity of contemporaneous data about IMS, we sought to evaluate clinical aspects and outcome of IMS in these patients.

METHODS

The records of adult haematological malignancy patients with proven or probable IMS over a 10 year period were reviewed retrospectively.

RESULTS

We identified 44 patients with IMS. Mucorales were isolated in 13 (35.1%) patients and Fusarium and Aspergillus were isolated in 9 (24.3%) patients each. Patients with IMS owing to Mucorales were more likely to have a history of diabetes mellitus (P = 0.003) and high-dose corticosteroid use (P = 0.03). Thirty-five (80%) patients received antifungal combinations and 36 (82%) underwent surgical debridement. The 12 week IMS-attributable mortality was 36.4% (16 patients). A relapsed and/or refractory haematological malignancy was an independent risk factor for 6 week IMS-attributable (P = 0.038), 12 week all-cause (P = 0.005) and 12 week IMS-attributable (P = 0.0015) mortality. Neutrophil count <100/µL and lymphocyte count <200/µL were associated with increased 12 week IMS-attributable and 6 week all-cause mortality, respectively (P = 0.044 and 0.013). IMS due to Aspergillus was an independent risk factor for both 12 week all-cause (P = 0.011) and IMS-attributable (P = 0.026) mortality. Initial antifungal therapy with a triazole-containing regimen was associated with decreased 6 week all-cause (P = 0.032) and IMS-attributable (P = 0.038) mortality. Surgery was not an independent factor for improved outcome.

CONCLUSIONS

Despite combined medical and surgical therapy, IMS had high mortality. Mortality risk factors were relapsed and/or refractory malignancy, cytopenia and Aspergillus infection in this study.

Healthcare-associated outbreaks due to Mucorales and other uncommon fungi

BACKGROUND

Healthcare-associated outbreaks of fungal infections, especially with uncommon and emerging fungi, have become more frequent in the past decade.

MATERIALS AND METHOD

Here, we reviewed the history and definition of healthcare-associated outbreaks of uncommon fungal infections and discussed the principles of investigating, containing and treatment of these outbreaks.

RESULTS

In case of these uncommon diseases, occurrence of two or more cases in a short period is considered as an outbreak. Contaminated medical devices and hospital environment are the major sources of these outbreaks. Care must be taken to differentiate a real infection from colonization or contamination. Defining and identifying cases, describing epidemiologic feature of cases, finding and controlling the source of the outbreak, treating patients, and managing asymptomatic exposed patients are main steps for outbreak elimination. These fungal outbreaks are not only difficult to detect but also hard to treat. Early initiation of appropriate antifungal therapy is strongly associated with improved outcomes in infected patients. Choice of antifungal drugs should be made based on spectrum, pharmacodynamic and pharmacokinetic characteristics and adverse effects of available drugs. Combination antifungal therapy and surgical intervention may be also helpful in selected cases.

CONCLUSIONS

A multidisciplinary approach and close collaboration between all key partners are necessary for successful control of fungal outbreaks.

A long-term survivor of disseminated Aspergillus and mucorales infection: an instructive case

Invasive fungal infections remain major causes of infection-related mortality in hematopoietic stem cell transplantation (HSCT) patients. Mixed infections and multiple organ involvement have been reported in these patients. Here, we report a case of mixed Aspergillus and Mucorales infection involving the lungs, brain, spleen and bone in a HSCT patient with relapsed acute myeloid leukemia, who finally improved with triple antifungal therapy and neurosurgical evacuation of brain abscesses. She was put on lifelong secondary prophylaxis with posaconazole with excellent compliance and no sign of toxicity despite over 10 years of drug administration. Serial galactomannan measurements and positron emission tomography/computed tomography were used and were helpful for disease activity monitoring. This is an instructive case of long-term survival after a severe combined mould infection.

Patient outcomes in a liver transplant program in Iran

OBJECTIVES

The first liver transplant program in Tehran was started at Tehran University of Medical Sciences in 2002. The purpose of this study was to evaluate patient outcomes in this program.

MATERIALS AND METHODS

From January 2002 to February 2013, there were 172 deceased-donor orthotopic liver transplants performed in 166 patients, including revision transplant in 6 patients. Outcomes were evaluated for 4 phases of the program: (1) phase 1 (2002 to 2005; 9 transplants); (2) phase 2 (2006 to 2009; 41 transplants); (3) phase 3 (2010 to 2011; 49 transplants); and (4) phase 4 (2012 to 2013; 73 transplants).

RESULTS

The most frequent indications for liver transplant included cryptogenic cirrhosis, autoimmune hepatitis, and hepatitis B and C cirrhosis. During the progression from phase 1 to 4, there were significant decreases in median cold ischemia time, operative time, and transfusions (platelets, packed red blood cells, and fresh frozen plasma). The most frequent complications included infection and acute rejection. The overall median follow-up for all patients was 26 months (range, 9-144 mo). Frequency of 1-month, 3-month, 1-year, and 2-year survival increased from phase 1 to 4. Kaplan-Meier plots showed significant improvement in patient survival from phase 1 to 4 (P ≤ .001). The most common causes of death were sepsis and bleeding.

CONCLUSIONS

Clinical outcomes with deceased-donor liver transplant may be improved with a cooperative multidisciplinary team, coordinated care from different specialties, increased experience, and modifications of anesthetic and surgical techniques. Comprehensive unified written protocols for preoperative, perioperative, and postoperative treatment may help improve outcomes after sufficient experience is achieved.

Cytomegalovirus reactivation and preemptive therapy after liver transplant

OBJECTIVES

Cytomegalovirus is the most common viral infection after orthotopic liver transplant. The purpose of the present study was to determine the incidence of cytomegalovirus reactivation in Iranian liver transplant recipients at our center and to evaluate outcomes with preemptive therapy with ganciclovir for pp65 antigenemia.

MATERIALS AND METHODS

There were 145 patients who had liver transplant and who survived > 2 weeks after transplant. All patients were evaluated for pp65 antigenemia weekly until 90 days after transplant. The diagnosis of cytomegalovirus reactivation was made when a recipient had pp65 antigenemia ≥ 1/50,000 leukocytes. In patients who had cytomegalovirus infection, preemptive therapy with ganciclovir (5 mg/kg, intravenous, twice daily) was started immediately after diagnosis and continued for ≥ 21 days and until cytomegalovirus antigen became undetectable on 2 consecutive tests.

RESULTS

All patients in our study were seropositive for cytomegalovirus before transplant. Follow-up at mean 27 ± 20 months (range, 5.2 to 80.6 mo) after transplant showed that 46 patients (32%) had cytomegalovirus reactivation at mean 56 ± 67 days after transplant (range, 12 to 445 d). There was a higher frequency of female patients in the cytomegalovirus reactivation than non-reactivation group (odds ratio, 2.3; P ≤ .02). The most common causes of liver failure in the cytomegalovirus reactivation group were autoimmune hepatitis, cryptogenic cirrhosis, and hepatitis B virus cirrhosis. There was no significant relation between cause of liver failure, use of steroids before or after transplant, and frequency of acute rejection and cytomegalovirus reactivation. Only 1 patient (2%) developed cytomegalovirus disease at 22 days after transplant, and this patient was treated successfully. There were 6 patients (13%) who developed a second episode of cytomegalovirus reactivation at median 43 days (range, 10 to 176 d) after the first episode; all 6 patients were treated successfully with ganciclovir.

CONCLUSIONS

Preemptive treatment with ganciclovir may be an effective approach against cytomegalovirus in seropositive recipients after liver transplant.

Application of fnbA gene as new target for the species-specific and quantitative detection of Staphylococcus aureus directly from lower respiratory tract specimens by real time PCR

Staphylococcus aureus is a significant cause of hospital-acquired pneumonia (HAP), particularly in mechanically ventilated patients. We used the fibronectin-binding protein A gene (fnbA) for the species-specific and quantitative detection of S. aureus directly from lower respiratory tract (LRT) specimens by a Taq Man real time PCR. For this reason, a total of 269 lower respiratory tract (LRT) specimens collected from patients with hospital-acquired pneumonia were assayed. Amplification of fnbA in serial dilutions ranged from 10(9) CFU/ ml to 10(2) CFU/ml. Standard curve of triplicate every dilution had slope 3.34±0.1 and R2>0.99 with SD 0.1. Based on these data, the sensitivity and specificity of the newly developed real time PCR targeting the fnbA gene were both 100%. The Cohen's Kappa test showed the Kappa value of 1.0. The fnbA gene is a potential marker for the species-specific detection of S. aureus and can be used to detect this bacterium in any clinical specimens by real time PCR. Moreover, this method reduces the time needed for quantitative detection of Staphylococcus aureus from LRT specimens to nearly 2 hours compared to 1 to 4 days for culture and provided sensitivity equal to or greater than culture.

Diagnostic value of interferon-gamma assay in tuberculosis pericardial effusions: study on a cohort of Iranian patients

Tuberculosis pericarditis as a potentially fatal complication of tuberculosis requires effective diagnosis and treatment. We evaluated the efficacy of interferon-gamma (IFN-gamma) and adenosine deaminase (ADA) for diagnosing tuberculosis pericarditis in a cohort of Iranian patients presenting with pericarditis. We enrolled 38 patients with presentation of pericarditis. All patients underwent diagnostic and therapeutic pericardiostomy with drainage and biopsy. Adenosine deaminase and interferon-gamma levels were determined in pericardial fluid samples of all patients. Pericardial tissue samples were submitted for histopathologic and microbiologic studies. Polymerase chain reaction (PCR) was performed on all pericardial fluid samples to detect Mycobacterium tuberculosis. From 38 patients with pericarditis, 7 cases were diagnosed as having tuberculosis pericarditis (18.4%). Mean concentration of interferon-gamma in tuberculosis group was significantly higher compared to non-tuberculosis group (69257 pg/l [range: 26600-148000] vs. 329 pg/l [range: 0-2200], P&lt;0.000). Receiver operating characteristic (ROC) curve showed a value of 14400 pg/l as the cutoff point with a sensitivity of 100% and specificity of 100% for diagnosing tuberculosis pericardial effusion. Adenosine deaminase was not found to be significantly higher in tuberculosis group in comparison with non-tuberculosis causes of pericardial effusion (35.7 [range: 9-69] vs. 36.03 [range: 8-420], P=0.28). In this study interferon-gamma showed to be a valuable diagnostic test for detection of tuberculosis pericarditis among a cohort of Iranian patients. We suggest using interferon-gamma to diagnose tuberculosis pericarditis to make diagnose in case of suspicion. While in this study, adenosine deaminase measurement did not prove to have the characteristics of an accurate diagnostic test for tuberculosis pericarditis.

Fever and psychosis as an early presentation of Brucella-associated meningoencephalitis: a case report

OBJECTIVE

To describe a case with Brucella-associated meningoencephalitis. In addition, we report drug-induced hepatotoxicity due to acyclovir.

CLINICAL PRESENTATION AND INTERVENTION

A young woman was admitted with fever and psychosis and neuroimaging findings indicative of meningoencephalitis. Serology was positive for Brucella. She was treated with doxycycline, rifampin, and trimethoprim-sulfamethoxazole.

CONCLUSION

This case reminds physicians in endemic regions to consider neurobrucellosis as a differential diagnosis in patients with any unexplained neurologic symptoms or atypical psychosis. Early diagnosis and treatment of neurobrucellosis will be helpful in decreasing the sequelae of this complication.

QuantiFERON-TB Gold In-Tube test for diagnosis of latent tuberculosis (TB) infection in solid organ transplant candidates: a single-center study in an area endemic for TB

BACKGROUND

The prevalence of Mycobacterium tuberculosis in transplant recipients is estimated to be 50 times higher than in the general population, with a mortality rate of around 40%. Diagnosis and treatment of latent tuberculosis (TB) infection (LTBI) is an essential strategy for TB control. In this study we compared the QuantiFERON-TB Gold In-Tube test (QFT) with the tuberculin skin test (TST) for detection of LTBI in solid organ transplant (SOT) candidates.

PATIENTS AND METHODS

Between March 2008 and September 2011, 187 transplant candidates, who were referred to the transplant clinic of Imam-Khomeini Hospital, were enrolled in the study. Patients were screened for LTBI with both QFT and TST. Twenty-three patients (12.3%) were excluded for failure to follow up. Concordance between the 2 tests, and variables associated with test discordance were assessed.

RESULTS

The mean age of patients was 40 years (range: 11-65) and male-to-female ratio was 1.2 (88/76). TST and QFT were positive in 26 (15.9%) and 33 (20.1%) patients, respectively. Five cases (3.1%) had indeterminate QFT. Overall agreement between QFT and TST was about 80% (k = 0.32, P-value = 0.0001).

CONCLUSION

Considering the fair overall agreement between the 2 tests, and greater ease of the QFT from the patient's point of view, QFT is recommended for detection of LTBI in SOT candidates.

Pulmonary Tuberculosis in Patients with HIV/AIDS in Iran

BACKGROUND

Pulmonary tuberculosis is still the most common form of tuberculosis in HIV infected patients having different presentations according to the degree of immunosuppression. This study appraised the impact of HIV infection on clinical, laboratory and radiological presentations of tuberculosis.

METHODS

The clinical, laboratory and radiological presentations of pulmonary TB in 56 HIV-infected patients were compared with 56 individually sex and age matched HIV-seronegative ones, admitted to Imam Hospital in Tehran (1999-2006) using paired t-test in a case control study.

RESULTS

All cases and the controls were male. Fever was found in 83.9% of the HIV positive patients compared to 80% of the HIV negative ones. Cough was the most common clinical finding in the HIV negative group (89.3% vs. 82.1% in HIV positive group). Among radiological features, cavitary lesions, upper lobe and bilateral pulmonary involvement were observed significantly less often in the HIV-infected group. On the contrary, lymphadenopathy was just present in the HIV positive group in this series of patients (12%) and primary pattern tuberculosis was more common, as well (71% vs. 39%, P= 0.02). The Tuberculin test was reactive in 29% of the HIV/TB patients.

CONCLUSION

The coexistence of both infections alters the picture of tuberculosis in many aspects and should be taken into account when considering a diagnosis of HIV infection and its potential for TB co-infection, and vice-versa.

Meningoencephalitis associated with hepatitis A infection: a case report and review of literature

Hepatitis A virus uncommonly causes neurological problems. Among these manifestations meningoencephalitis is very rare. We describe the clinical and laboratory features of a young boy with hepatitis A associated meningoencephalitis and compare it with other cases which had the same diagnoses.

Prevalence of hepatitis A virus infection in a HIV positive community

Hepatitis A is acute and usually self-limiting disease, but sometimes it can be dangerous such as in immunosuppressed patients. Purpose of this study is to investigate the prevalence of hepatitis A serology in HIV/AIDS Patients. 247 HIV positive patients from March 2005 to September 2006 were entered in this study. Participants completed questionnaires to elicit demographic, drug and sex risk information, and were (tested for hepatitis A. They were all referred to Counseling center for behavioral diseases in Imam Khomeini Hospital. Cases were chosen from volunteers with no history of jaundice or acute hepatitis. Data were analyzed by SPSS version 13 and results were compared between seropositive and seronegative groups using T test and chi square. Statistical significance was accepted at a level of P < 0.05.200 (80.98%) were male and 47 (19.02) were female. The mean age was 36 +/- 9.3. 238 (96.3%) of patients were seropositive. One hundred percent and 96% who were born in rural and urban areas were seropositive, respectively. Also, 85.7% and 96.6% who reside in rural and urban areas were seropositive, respectively. Iran is an endemic country for hepatitis A in which most people has asymptomatic infectious during childhood. According to high prevalence of hepatitis A positive serology in HIV/AIDS patients, routine vaccination seems to be unnecessary. But special sub populations like HIV infected infants should be evaluated more precisely and different approaches may be needed for them.

Soy-diet has beneficial effects on cardiovascular parameters that are independent of its lipid effect in male hypercholesterolemic rats

Diet-induced atherosclerosis is lower in animals fed soy protein. The effects of various soy components have been extensively studied; however, little is known about the effect of crude soybean feeding on hypercholesterolemia-induced cardiovascular changes. This study investigated the effect of soy feeding on cardiovascular parameters in hypercholesterolemic male rats. Total cholesterol (TC), low density lipoprotein (LDL) and high density lipoprotein cholesterol (HDL), and triglyceride (TG) were measured. Rats were randomly assigned to control, high cholesterol (HC, 2% cholesterol) or HC + soy (HC+S) diets. In the HC+S group, rats received HC diet for 10 weeks followed by 2 weeks of soybean feeding. Arterial blood pressure, TC, TG, LDL and HDL were measured. TC, TG and LDL were higher in HC rats and were not significantly reduced by soybean feeding. Soy feeding reversed the HC-induced increase in arterial blood pressure and also restored the impaired vascular responses to acetylcholine in isolated aortic rings. Pre-incubation of HC+S aortic rings with L-NAME (10(-5) M for 20 min) partially reduced the effects of soy on acetylcholine responses, indicating that the beneficial vascular effects of dietary soy are partially mediated via nitric oxide pathway.

Th-1 cytokines gene polymorphism in human brucellosis

Brucellosis is a worldwide zoonosis. Infection with Brucella species results in the activation of cell-mediated immune response. The interaction between Th1and Th2 cytokines determines the outcome of disease. Production of each cytokine is in turn affected by genetic factors. In this study, we investigated the possible association between Th1 cytokines gene polymorphism and brucellosis. Different genotypes of TNF-alpha, IFN-gamma and IL-2 were determined by polymerase chain reaction-sequence-specific primer in 47 patients with brucellosis and in 166 healthy controls. Allele frequencies of these genotypes were compared using the chi2 test. The results showed a significant difference in the TNF-alpha genotype GG/GG in patients in comparison with controls (76.7% vs. 21%) (P = 0.001, OR = 12.42, 95%CI 5.7-27.7). There was no significant difference in the frequency distribution of the IFN-gamma genotypes between two groups. IL-2 GG genotype at position -330 was about two times more common in cases than in controls, but the difference was not significant (10.6 vs. 4.6 P value = 0.09). This study shows that genetically low producers of TNF-alpha are possibly susceptible to brucellosis and raise doubt about the role of gene polymorphism of INF-gamma in brucellosis which was demonstrated in previous studies. It seems that patients with brucellosis did not have a defect in producing IL-2 with even a trend towards producing higher amounts of this cytokine.