Antimicrobial resistance rates of Enterobacter spp.: a seven-year surveillance study

OBJECTIVE

The aim of the study was to evaluate the trends of antimicrobial resistance of Enterobacter spp. over time in a Saudi Arabian hospital.

MATERIALS AND METHODS

This is an in vitro surveillance study of the antibiotic susceptibility pattern among Enterobacter spp. recovered from outpatient and nosocomial isolates over a 7-year period from 2000 to 2006. Only a single isolate per patient was included.

RESULTS

A total of 1,394 nonrepetitive isolates were analyzed during the study period. Enterobactercloacae and Enterobacteraerogenes constituted 60 and 33% of the isolates, respectively. Overall, there was no statistically significant increase in the resistance rates over time for the outpatient and nosocomial isolates of Enterobacter. For E.cloacae, nosocomial isolates were statistically more resistant than outpatient isolates to ceftriaxone (17.5 vs. 5.5%), ciprofloxacin (9.5 vs. 4.7%), ticarcillin (42.8 vs. 25.4%) and ticarcillin-clavulanic acid (23 vs. 9.3%). For E.aerogenes, the nosocomial isolates were also more resistant to ceftriaxone and ciprofloxacin than the outpatient isolates (9.2 vs. 2.4% and 9.6 vs. 3%, respectively). In addition, nosocomial isolates of E.aerogenes were more resistant to piperacillin (25 vs. 15.6%) and ticarcillin-clavulanic acid (32 vs. 10.2%) than outpatient isolates. The most active antimicrobial agents were imipenem, amikacin and gentamicin against Enterobacter. Resistance rate to >or=3 classes of antibiotics was present in 2.5% of nosocomial and 1.7% of outpatient isolates (p = 0.78).

CONCLUSION

The resistance rate for the outpatient and nosocomial isolates of Enterobacter had remained relatively stable over the study period. The most active antimicrobial agents were imipenem, amikacin and gentamicin.

Listeria monocytogenes bacteremia in a twin pregnancy with differential outcome: fetus papyraceus and a full-term delivery

A 41-year-old Saudi woman, gravida 7, para 5, aborta 1 with sickle cell disease at week 12 of gestation of diamniotic dichorionic twin pregnancy was admitted with fever. Blood cultures grew Listeria monocytogenes. She was treated with intravenous ampicillin and had death of one of the fetuses after 10 days. An ultrasound at 19 weeks of gestation showed a normal intrauterine gestation and the presence of significantly collapsed second twin gestational sac consistent with fetal papyraceus. At 37 weeks of gestation, she had a cesarean section and a full-term baby was delivered. We describe the case and review the literature on pregnancy-associated listeriosis.

Therapeutic options for human brucellosis

Worldwide, human brucellosis is the most common zoonotic disease and it has gained increasing interest because of the potential use of Brucella as a biological weapon. Monotherapy for brucellosis is associated with a high relapse rate and dual therapy in different combinations is more efficacious. The combination regimen of intramuscular streptomycin with an oral tetracycline resulted in fewer relapses than the doxycycline-rifampin combination in meta-analysis and prospective studies, although the use of doxycycline and rifampin is a reasonable choice in certain conditions. Longer duration and triple antimicrobial therapy appear to improve outcome and prevent relapses, especially in patients with focal disease. Recently, the use of gentamicin-loaded microparticles and the use of new antibiotics, such as tigecycline, may hold future promise. In addition, there are a few studies of the enhanced effect of immune response stimulators, such as levimasole and IFN-2, in the treatment of brucellosis. The development of an effective subcellular Brucella vaccine would be an important step forward to curtail the disease. However, currently and for the near future, only the control of animal disease is possible using vaccine strategies.

Transfusion-transmitted malaria in a kidney transplant recipient. How safe is our blood transfusion?

A 51-year-old male patient with living, unrelated kidney transplantation in Iran in June 2001, developed Plasmodium falciparum P. falciparum infection. He was maintained on cyclosporine A, mycophenolate mofetil, and prednisone. In August 2005, he was admitted to a medical facility in the local community with upper gastrointestinal bleeding, and received several units of blood and blood products. Two months later, he was referred to Dhahran Health Center, and admitted with fever, abdominal pain, dysuria, and severe fatigue. Plasmodium falciparum with a parasitemia of 70% was detected in the peripheral smear. He was treated with intravenous quinidine gluconate and oral doxycycline, in addition to blood transfusion, and he responded well to the treatment. An investigation was carried out to try to find the source of malaria infection, which is believed to be the blood or blood products that he received during his initial acute illness. Measures to minimize transfusion related malaria are discussed.

Bacteroides fragilis bacteremia associated with vertebral osteomyelitis in a sickle cell patient

Osteomyelitis and septic arthritis are serious complications of sickle cell disease which occur at rates of 18% and 7%, respectively. In two small studies of osteomyelitis in sickle cell patients, the most common causative organisms were Salmonella spp. and Staphylococcus spp. Anaerobic infection is uncommon. Here, we report an 18-year-old girl with sickle cell disease and suspected spontaneous vertebral osteomyelitis due to Bacteroides fragilis. The diagnosis was based on multiple positive blood cultures. Despite extensive investigation, the port of entry could not be determined. The patient responded well to a four-week therapy with metronidazole, without the need for surgical debridement.

Bacteroides (Parabacteroides) distasonis splenic abscess in a sickle cell patient

Splenic abscess is not an uncommon complication of patients with sickle-cell disease. Here we describe an 18 year-old boy with sickle cell disease and left upper quadrant abdominal pain. Computerized axial tomography revealed left sided free flowing pleural effusion and splenomegaly with liquefaction and possible gas formation. The splenic fluid grew an unusual organism known as Bacteroides distasonis. The patient received antimicrobial therapy and underwent a splenectomy with full recovery. The spleen was cystically infarcted and measured 22 x 16 x 5 cm. The capsule was thickened and covered by fibrinous exudate. Histopathologic examination of the spleen showed complete necrosis with reparative fibrosis. This case presents an unusual cause of splenic abscess due to Bacteroides distasonis with a subacute to chronic course. The presence of fever and left sided pleuritic chest pain in patients with sickle cell disease should raise the suspicion of splenic abscess.

Profile of viral hepatitis A, B, and C in a Saudi Arabian hospital

BACKGROUND

The objective of the study was to investigate the pattern and epidemiology of viral hepatitis among patients of the Saudi Aramco Medical Services Organization (SAMSO) in the Eastern Province of Saudi Arabia.

MATERIAL/METHODS

A retrospective analysis of the reported cases of viral hepatitis was conducted from January 2000 to June 2005.

RESULTS

A total of 1214 patients with viral hepatitis were identified during the study period. Of hepatitis A, B, and C, HBV was the most predominant type of hepatitis, accounting for 49.3% of the cases, followed by HCV (40.7%) and HAV (10%). Nine (0.7%) patients had both HBV and HCV. The male-to-female ratio was higher in HBV (1.8:1), whereas HAV and HCV showed no significant differences. HAV infection predominates in children (1-20 years), HBV in young adults (31-50 years), and HCV in older adults (51-70 years).

CONCLUSIONS

HBV continues to be the most predominant type of viral hepatitis and is a disease of adults, whereas HCV is mainly a disease of older adults. Continued surveillance of hepatitis cases is needed to further delineate the risk factors and to establish effective preventive strategies.

Spontaneous remission of acute monocytic leukemia after infection with Clostridium septicum

Spontaneous remissions of acute myeloid leukemia (AML) have been reported in association with infection. Here, we report a case of spontaneous remission of AML in a 47-year-old Saudi Arabian male patient who presented with a few weeks history of recurrent abdominal pain, vomiting and fever. He was diagnosed with acute monocytic leukemia (AML, FAB M5b) and a perforated bowel. He also had Clostridium septicum bacteremia and thus chemotherapy was deferred. He received supportive therapy and intravenous antibiotics. Six weeks later, he achieved spontaneous and complete remission lasting for about 4 months. The remission and relapse were documented by bone marrow examination. Similarly, previous reports of spontaneous remission of AML were short lived and were followed by relapse and progression.

Cryptococcus neoformans abscess and osteomyelitis in an immunocompetent patient with tuberculous lymphadenitis

Infection with Cryptococcus neoformans usually occurs in immunocompromised hosts and may occur in immunocompetent patients. Of all cryptococcal infections, 10-40% of patients have no apparent immune deficiency. Disseminated disease may occur in up to 62% of HIV-seronegative patients with cryptococcosis; however, cryptococcal osteomyelitis is rare. Here, we report an immunocompetent patient with cryptococcal vertebral osteomyelitis and concomitant tuberculous lymphadenitis. The patient received 12 weeks of fluconazole and a 1-year course of anti-tuberculous agents, with complete recovery.

Antimicrobial resistance of Klebsiella pneumoniae in a Saudi Arabian hospital: results of a 6-year surveillance study, 1998-2003

There are few data regarding the prevalence and trends of antibiotic resistance to Klebsiella pneumoniae in Saudi Arabia over time. Thus, we evaluated the prevalence and the trends in antibiotic resistance of K. pneumoniae at the Saudi Aramco Medical Services Organization over a 6-year period. This was a retrospective study of the in vitro pattern and trends of antibiotic resistance of K. pneumoniae from 1998 to 2003. A total of 3070 distinct isolates of K. pneumoniae were analyzed. Hospital-acquired isolates were more resistant to the tested antibiotics than the outpatient isolates. The resistance rates to cefazolin, trimethoprim-sulfamethoxazole, and ciprofloxacin were 10.8% (n = 79/730), 5% (n = 103/2093), and 15.8% (n = 93/586) for hospital-acquired isolates; and 11% (n = 216/1964), 9.6% (n = 60/624), and 4.4% (n = 68/1526) for outpatient isolates. Resistance to ceftriaxone and ceftazidime was detected in 5.6% (n = 37/659) and 13.8% (n = 24/174) of hospital-acquired isolates and in 1% (n = 17/1713) and 2.7% (n = 6/219) of outpatient isolates, respectively. All tested isolates were susceptible to imipenem. Resistance to three or more classes of antibiotics was present in 1.7% (n = 8/468) of the hospital-acquired isolates and in 0.6% (n = 9/1389) of the outpatient isolates. The data showed increased resistance rates of hospital-acquired isolates of K. pneumoniae to ceftriaxone, gentamicin, and ciprofloxacin; the data also showed that hospital-acquired, rather than outpatient isolates, were more likely to be resistant to multiple antibiotics.

Prevalence of antimicrobial resistance in Acinetobacter calcoaceticus-baumannii complex in a Saudi Arabian hospital

During the period from 1998 through 2004, a total of 476 isolates of Acinetobacter calcoaceticus-baumannii complex were recovered. The organism showed high rates of resistance to ampicillin (86% of isolates), cefoxitin (89%), and nitrofurantoin (89%). The rate of resistance to imipenem was 3%; to ticarcillin-clavulanic acid, 16.5%; to gentamicin, 26%; and to ceftazidime, 38%. Multidrug resistance was observed in 14%-35.8% of Acinetobacter species isolates.

Multifocal systemic tuberculosis: the many faces of an old nemesis

BACKGROUND

Tuberculosis continues to be a major health problem, where an estimated 7-8 million new cases are diagnosed each year. Multifocal tuberculosis is characterized by the presence of large multifocal tuberculous areas in the same or different organs. Difficulty in diagnosis of multifocal tuberculosis and consideration of other diseases may lead to a delay in diagnosing this entity. Here the clinical features and characteristics of three patients with multifocal systemic tuberculosis are described.

CASE REPORT

During the period of 1999-2005, a total of 128 confirmed cases of tuberculosis were identified. Three (2.3%) patients had multifocal systemic tuberculosis. The first case had involvement of the lung, psoas muscle, and the vertebral bodies. The second patient had multiple brain lesions with mediastinal and retroperitoneal lymphadenopathy. The third patient had multiple brain lesions, lymphadenopathy, and colonic lesions initially mimicking a metastatic disease. Mycobacterium tuberculosis was grown from pleural fluid in one patient and from lymph node biopsies in another patient. The third patient had histopathologic evidence of tuberculosis. All patients received standard anti-tuberculous treatment, resulting in a full recovery in two patients, while the third patient had residual weakness.

CONCLUSIONS

Multifocal systemic tuberculosis may pose a diagnostic challenge and may occur in immunocompetent hosts, in whom this entity generally has a good outcome.

Granulicatella elegans native valve infective endocarditis: case report and review

Granulicatella elegans is a fastidious organism that is rarely implicated as a cause of infective endocarditis. Here, we describe a patient with mitral valve prolapse who developed G. elegans endocarditis. The organism was isolated from blood cultures and the patient had mitral valvuloplasty and repair, and completed a course of 6 weeks of intravenous antibiotics with no sequela.

Occurrence and antimicrobial resistance pattern of inpatient and outpatient isolates of Pseudomonas aeruginosa in a Saudi Arabian hospital: 1998–2003

OBJECTIVES

The objective of this study was to describe the pattern and trends of antibiotic resistance of Pseudomonas aeruginosa over a six-year period in a Saudi Arabian hospital.

METHODS

This was a retrospective study of the antibiotic resistance of outpatient and inpatient isolates of P. aeruginosa. Only one isolate per patient per year was included in the study.

RESULTS

During the study period a total of 2679 isolates of P. aeruginosa were available for analysis. Outpatient isolates constituted 48% of the total number, and of these 23.4% were obtained from wound cultures. For the inpatient isolates, 33.6% and 30% were obtained from the respiratory tract and wounds, respectively. There was no significant increase in the resistance rates of outpatient isolates to the tested antibiotics over time. On the other hand, inpatient isolates showed a statistically significant increase in resistance rates to piperacillin, ceftazidime, imipenem, and ciprofloxacin (p<0.001). Over the study period, the resistance rates of outpatient and inpatient isolates to piperacillin, ceftazidime, imipenem, and ciprofloxacin were 4.6% and 11.5%, 2.4% and 10%, 2.6% and 5.8%, and 3% and 6%, respectively. Gentamicin demonstrated the highest resistance among all tested aminoglycosides for outpatient isolates (6%) and inpatient isolates (6.7%). Resistance to more than two classes of antibiotics was present in 1-2% of inpatient isolates and in 0% of outpatient isolates.

CONCLUSION

Antibiotic resistance continues to be a problem especially in inpatient isolates and is likely to be related to increased antibiotic use. Thus, continued monitoring of antibiotic resistance is of great importance to ensure the proper use of antibiotics and to detect any increasing trends in resistance.

Haemophilus influenzae type e meningitis and bacteremia in a healthy adult

Haemophilus influenzae type b causes more than 95% of serious H. influenzae meningitis. H. influenzae type e (Hie) has been implicated in a few cases of meningitis. Here, we present an adult Saudi patient with Hie meningitis and review the literature. The patient, a 19-year-old Saudi male with no significant past medical history, was noted by his family to have some changes in his mentation, confusion and refusal to eat; subsequently, he became unresponsive. Cerebrospinal fluid and blood culture grew Hie. The patient was treated with intravenous ceftriaxone with full recovery.

Antibiotic resistance of pediatric isolates of Streptococcus pneumoniae in a Saudi Arabian hospital from 1999 to 2004

BACKGROUND

This study describes the resistance pattern of Streptococcus pneumoniae isolates obtained from pediatric patients in a Saudi Arabian hospital.

MATERIAL/METHODS

This is a retrospective analysis of the antibiotic resistance of S. pneumoniae isolates (n=141) obtained from children in a Saudi Arabian hospital 1999-2004. Clinical data and antibiotic sensitivity were retrieved from microbiology data and analyzed.

RESULTS

Of the total isolates of S. pneumoniae, 57.6% were susceptible to penicillin, 28.8% intermediately susceptible, and 13.7% were resistant organisms. Over the study period, high-level penicillin resistance of S. pneumoniae was 0% in 1999, 23% in 2001, and 3.4% in 2004. Intermediate penicillin resistance was 21% in 1999, 41% in 2001, and 27.6% in 2004. The resistance rates to other antibiotics were as follows: erythromycin 33.4%, tetracycline 30%, trimethoprim-sulfamethoxazole 40%, and clindamycin 21.6%. Children less than 2 years of age showed a higher rate of intermediately penicillin-susceptible isolates (41.9% versus 22.7%, P=0.0.02). They also had higher rates of resistance to tetracycline (42.4% versus 25%, P=0.03), trimethoprim-sulfamethoxazole (54% versus 33.8%, P=0.02), and clindamycin (33% versus 17%, P-0.04). All tested isolates were susceptibility to ceftriaxone and vancomycin.

CONCLUSIONS

The overall high-level penicillin resistance of S. pneumonaie from 1999-2004 was 13.7%. The percentage of intermediately penicillin-susceptible organisms was higher in the age group under 2 years of age (41.9%) than in patients 2 years of age or older (22.7%).

Incidence and epidemiology of methicillin-resistant Staphylococcus aureus infection in a Saudi Arabian Hospital, 1999-2003

During 1999-2003 in a Saudi Arabian Hospital, methicillin-resistant Staphylococcus aureus constituted 6% of all S. aureus isolates; the proportion had increased from 2% in 1999, to 9.7% in 2002, to 8% in 2003. Of all MRSA isolates, 62% represented community-acquired infection, 20.4% represented healthcare-associated infection, and 17.6% represented nosocomial infection. The proportion of community-acquired isolates increased from 41.7% in 1999 to 66.6% in 2002, and the proportion representing nosocomial infection decreased from 33% in 1999 to 19% in 2003. Isolates representing nosocomial infection showed higher rates of resistance to ciprofloxacin (76.6%), clindamycin (76.6%), erythromycin (68%) and trimethoprim-sulfamethoxazole (68%) than did isolates in the other categories (P<.001).

Distribution and epidemiology of Candida species causing fungemia at a Saudi Arabian hospital, 1996-2004

OBJECTIVES

The objective of this study was to evaluate the Candida species and the change over time in the organisms causing candidemia at Saudi Aramco Medical Services Organization in Saudi Arabia. We also describe the risk factors associated with mortality.

METHODS

This was a retrospective study of candidemia over nine years (1996-2004).

RESULTS

A total of 98 distinct episodes of candidemia were identified over the study period. The annual incidence of candidemia ranged between 0.2 and 0.76 cases/1000 hospital discharges with an incidence per 10 000 patient-days per year of 0.45 to 1.6. The most frequent Candida species were Candida albicans (53%), Candida tropicalis (19%), Candida parapsilosis (16%), and Candida glabrata (7%). In relation to predisposing factors, 83% of candidemia occurred in patients with central venous catheters and 96% had received broad-spectrum antibiotics. Other predisposing factors included complicated abdominal surgeries (22%), total parenteral nutrition (52%), neutropenia (9%), acute renal failure (24%), malignancy (26%) and burns (15%). However, prior fluconazole use was low (8%). The overall crude mortality rate was 43% for all candidemia. Logistic regression analysis identified two independent determinants of death, C. albicans (OR 5.91, 95% CI 1.50, 23.24, p=0.01) and acute renal failure (OR 5.15, 95% CI 1.18, 22.55, p=0.03).

CONCLUSION

The study showed that the rate of candidemia was low in our hospital and that C. albicans was the major species followed by C. tropicalis and C. parapsilosis. Future studies are needed to evaluate the antifungal susceptibility pattern in our hospital.

Increasing antibiotic resistance among isolates of Escherichia coli recovered from inpatients and outpatients in a Saudi Arabian hospital

OBJECTIVE

To study the pattern of antibiotic resistance among Escherichia coli and the trend in resistance during a 6-year period in a Saudi Arabian hospital.

DESIGN

Retrospective in vitro surveillance study of the antibiotic susceptibility pattern among E. coli isolates recovered from outpatients and from inpatients.

SETTING

A general hospital in Saudi Arabia.

PATIENTS

All patients with a culture positive for E. coli during a 6-year study period.

RESULTS

A statistically significant increase in antibiotic resistance was observed among outpatient and inpatient isolates of E. coli. Inpatient isolates were more likely to be resistant to antimicrobial agents. Among isolates from outpatients, 50% were resistant to ampicillin, 33% were resistant to trimethoprim-sulfamethoxazole (TMP-SMZ), and 14% were resistant to ciprofloxacin. Among isolates from inpatients, 63% were resistant to ampicillin, 44% were resistant to TMP-SMZ, and 33% were resistant to ciprofloxacin. There was a low rate of resistance to imipenem (0.3% of isolates), amikacin (2%), and nitrofurantoin (2.4%-6.5%). Resistance to ceftazidime was detected in 9% of outpatient isolates and 17% of inpatient isolates. Multidrug resistance was defined as resistance to 2 or more classes of antibiotics. Multidrug resistance was detected in 2.0%-28.1% of outpatient isolates and 7.4%-39.6% of inpatient isolates, depending on the combination of antimicrobials tested. More isolates were resistant to ampicillin plus TMP-SMZ than to any other combination of antimicrobials.

CONCLUSION

The prevalence of antibiotic resistance among outpatient and inpatient E. coli isolates increased during the study period. The rates of antibiotic resistance were statistically significantly higher among inpatient isolates, compared with outpatient isolates. These findings call for wiser use of antibiotics and continued surveillance of antibiotic resistance.

Brucella epididymo-orchitis: a consideration in endemic area

Brucellosis is a zoonotic disease caused by Brucella sp. and may affect many parts of the body. Brucella epididymo-orchitis had been reported in up to 20% of patients with brucellosis. This is a case report of Brucella epididymo-orchitis in a Saudi male patient. He presented with a unilateral swelling of the left testicle. He had fever, arthralgia and night sweats. Ultrasound examination revealed enlarged left epididymis and testicle. Brucella serology was positive and the patient responded to treatment with doxycycline and gentamicin. Thus, brucella infection should be considered in the differential diagnosis of patients presenting with epididymo-orchitis from an endemic area.

Father-to-infant transmission of community-acquired methicillin-resistant Staphylococcus aureus in a neonatal intensive care unit

Methicillin-resistant Staphylococcus aureus (MRSA) is increasingly being recognized as a cause of community-acquired infection. Its transmission in neonatal intensive care units (NICUs) has reportedly been linked to a few cases of community-acquired MRSA (CA-MRSA) infection. Here, I describe a case of CA-MRSA transmission from a father to his child in a NICU. Recognition that CA-MRSA may be transmitted in a hospital setting raises important issues for MRSA infection control and treatment options.

Epidemiology and outcome of severe hepatitis A infection in children in Kuwait

OBJECTIVE

To describe the epidemiology, clinical features and outcome of hepatitis A virus (HAV) infection in children in Kuwait.

SUBJECTS AND METHOD

The medical records of 350 patients (age 0-16 years) admitted to the Infectious Diseases Hospital, Kuwait, between January 2000 and December 2002, with hepatitis A infection were reviewed.

RESULTS

The mean age was 8.6 +/- 3.8 years and 47% of patients were between 7 and 12 years old. Kuwaiti children comprised 44% of admitted patients. The largest proportion of children with hepatitis A (34%) were from the northern part of the country. HAV infection was prevalent throughout the year with a peak during the months of August to October. Of the Kuwaiti children, 31% reported a history of contact with jaundiced patients, while 52% of the non-Kuwaiti children had a history of recent travel prior to their illness. Patients had symptoms for a mean of 6 +/- 3.6 days prior to presentation. The mean length of hospitalization was 5.8 +/- 2.9 days. The rate of complications of HAV infection was 6% and only one child required admission to the intensive care unit for fulminant hepatitis. None of the patients had permanent sequelae.

CONCLUSIONS

HAV infection is a significant cause of morbidity for children in Kuwait. The disease is mostly prevalent in preschool and school age children. Despite the excellent outcome of all patients, a considerable number of patients tend to have a complicated course and prolonged hospitalization. In view of these data, hepatitis A vaccine should be considered as a part of routine childhood immunization in Kuwait.

Epidemiology of travel-related malaria in a non-malarious area in Saudi Arabia

OBJECTIVE

The study describes the epidemiology of malaria in the Eastern Province of Saudi Arabia and the species of Plasmodium causing the disease and the associated factors.

METHODS

This is a retrospective study of the epidemiology of malaria at Saudi Aramco Medical Services Organization in Dhahran, Eastern Province of Saudi Arabia. The study included all patients with malaria from January 1994 to June 2005. We retrieved the cases from the archive epidemiology records on all notifiable diseases. The medical records of patients were reviewed and the following information was collected: age, gender, nationality, year and month of acquisition, travel history and the species causing malaria.

RESULTS

Over the study period from January 1994 to June 2005, there were 56 cases of imported malaria seen at Saudi Aramco Medical Services Organization. There were 28 males and 28 females with a mean age of 28.2 +/- 19.7 (range, 1-80) years. Saudis constituted 25% of the patients and the remaining (75%) were non-Saudi. Most of the cases (78.7%) were acquired outside Saudi Arabia and 21.3% were acquired in the Kingdom but outside the Eastern Province. The most frequent species were Plasmodium vivax (P. vivax) (54.4%), Plasmodium falciparum (P. falciparum) (43%) and Plasmodium malariae (1.8%). Of the cases acquired within other parts of Saudi Arabia, 71.4% were secondary to P. falciparum. Acquisition of malaria in India P. falciparum constituted 71.4% and in Pakistan 91%. For Sudanese patients, P. falciparum constituted 47% and P. vivax was 53%. Most of the non-Saudi cases were seen in the month of September (19%) whereas 57% of the Saudi cases were seen in February and April.

CONCLUSION

There were no active cases of malaria transmission within the Eastern province of Saudi Arabia; however, the continued presence of imported malaria into this region may pose a significant health problem especially in the presence of the malaria vector. Thus, effective treatment and vigilance for cases of malaria is needed.

Community-acquired MRSA bacteremic necrotizing pneumonia in a patient with scrotal ulceration

Methicillin-resistant Staphylococcus aureus (MRSA) is being recognized increasingly as a cause of community-acquired infection. The organism usually causes skin and soft tissue infection. Here, we present a patient with community-acquired MRSA pneumonia and review the literature. The patient, a 37-year-old Saudi male with no significant medical history was admitted with fever, respiratory distress and scrotal ulceration. Scrotal swabs and blood cultures grew MRSA. Imaging studies showed necrotizing pneumonia. Physical examination and echocardiographic findings revealed no evidence of endocarditis. The patient was treated successfully with 4 weeks of intravenous vancomycin. The infection appears to have originated in the skin and subcutaneous tissues of the scrotum, and subsequently led to necrotizing pneumonia. Community-acquired MRSA pneumonia has been associated with the production of Panton-Valentine leukocidin.

Susceptibility Pattern and Epidemiology of Mycobacterium tuberculosis in a Saudi Arabian Hospital

OBJECTIVES

The objective of this study was to examine the prevalence and trends of drug resistance of Mycobacterium tuberculosis at the Saudi Aramco Medical Services Organization.

METHODS

We retrospectively identified M tuberculosis isolates from January 1989 to December 2003. Antimicrobial susceptibility and clinical data were collected and analyzed.

RESULTS

From 1989 to 2003, 276 nonrepetitive culture-positive cases were identified. There were 236 Saudis (84.6%), and the remainder were non-Saudis (15.4%). M tuberculosis isolates were obtained from pulmonary specimens (49%) and extrapulmonary sites (51%). The resistance rates of M tuberculosis to tested first-line agents were as follows: isoniazid, 12.5%; ethambutol, 7.5%; streptomycin; 6.9%; and rifampin, 1.1%. The resistance rate to isoniazid and streptomycin was 1.8%, the rate to isoniazid and rifampin was 0.7%, and the rate to isoniazid and ethambutol was 2.5%. The resistance rate to isoniazid, ethambutol, and streptomycin was 0.7%

CONCLUSION

M tuberculosis resistance to isoniazid showed a decreased rate over the study period from 20 to 5.7%. The rate of multidrug-resistant M tuberculosis remained low.

Invasive Fungal Infections in Living Unrelated Renal Transplantation

In many developing countries, renal transplantation from paid, unrelated donors constitutes the main type of renal transplantation. Several medical and social problems are likely to occur in association with this practice. Among the many medical complications, invasive fungal infections are the most feared. In this report, we describe our experience with 3 patients who underwent living unrelated renal transplantation (LURTX) and developed this complication. One patient developed disseminated mucormycosis, 1 developed invasive aspergillosis (IA), and the third developed central nervous system (CNS) infection with Ramichloridium mackenziei. Two died within a few months after the diagnosis, whereas the third developed hemiplegia and is debilitated.

Successful therapy of cerebral phaeohyphomycosis due toRamichloridium mackenzieiwith the new triazole posaconazole

Cerebral phaeohyphomycosis caused by Ramichloridium mackenziei is universally fatal. All reported cases with long-term follow-up have indicated 100% mortality despite antifungal therapy and surgical intervention. We describe the case of a 62-year-old patient who underwent renal transplantation and had a cerebral abscess caused by R. mackenziei. The infection progressed despite surgical evacuation and therapy with liposomal amphotericin B, itraconazole, and 5-flucytosine. The patient was subsequently treated with the investigational triazole posaconazole oral suspension, 800 mg/day, in divided doses. Treatment with posaconazole resulted in progressive clinical and radiologic improvement. The patient is alive four years after diagnosis and maintained on posaconazole therapy. This case supports the potential role of this extended-spectrum azole in the treatment of this serious fungal infection of the central nervous system.

Cutaneous leishmaniasis: a 46-year study of the epidemiology and clinical features in Saudi Arabia (1956-2002)

OBJECTIVE

The aim of this study was to evaluate the epidemiology of cutaneous leishmaniasis in the Eastern Province of Saudi Arabia. In addition, the clinical spectrum of the disease was evaluated.

METHODS

This is a retrospective study of cutaneous leishmania cases from 1956 to 2002.

RESULTS

In the study period, there were 1862 patients with cutaneous leishmaniasis in the Saudi Aramco health care system. The disease is more prevalent in the Al-Hasa Oasis (Eastern Province of Saudi Arabia) and affects males and females equally. Cutaneous leishmaniasis follows a seasonal distribution in parallel with the known activity of the sandfly. The majority (76%) of cases occurred in patients < 15 years of age and the disease affected the extremities more frequently than the face. Seventy-one percent of patients presented with a single lesion and 27% presented with two lesions. Ulcerative cutaneous leishmaniasis was the predominant morphology (89%).

CONCLUSION

Cutaneous leishmaniasis attained epidemic proportions in 1973 and subsequently declined and reached a plateau in the mid-1980s. Skin involvement is the major clinical picture, with no evidence of dissemination or viscerotropic syndrome.

Haemophilus ducreyi: clinical disease and pathogenesis

Haemophilus ducreyi causes the sexually transmitted disease chancroid, which facilitates the transmission of HIV infection. This review focuses on recent advances in the epidemiology, diagnosis, treatment and pathogenesis of this disease.

Evaluation of an isogenic major outer membrane protein-deficient mutant in the human model of Haemophilus ducreyi infection

Haemophilus ducreyi expresses 2 OmpA homologs, designated MOMP and OmpA2, whose genes are arranged in tandem on the chromosome. Northern blot analysis indicated that momp and ompA2 are transcribed independently. Sequences of the momp open reading frame (ORF) lacking the transcriptional start site were amplified by PCR, and an Omega-Km2 cassette was ligated into the ORF. A plasmid containing this construction was electroporated into H. ducreyi 35000HP, and an isogenic MOMP-deficient mutant (35000HP-SMS2) was generated by allele exchange. In Southern blotting, 35000HP-SMS2 contained one copy of the Omega-Km2 cassette in momp. 35000HP and 35000HP-SMS2 had similar outer membrane protein (OMP) and lipooligosaccharide profiles and growth rates except for up-regulation of a putative porin protein in the mutant. Five subjects were inoculated with three doses of live 35000HP-SMS2 on one arm and two doses of live 35000HP and one dose of a heat-killed control on the other arm in a double-blind escalating dose-response trial. Pustules developed at 7 of 10 sites inoculated with 35000HP and at 6 of 15 sites inoculated with 35000HP-SMS2 (P = 0.14). 35000HP and 35000HP-SMS2 were recovered at similar rates from daily surface cultures and semiquantitative cultures. The data suggest that expression of MOMP is not required for pustule formation by H. ducreyi in the human model of infection.

Pyomyositis in the acquired immunodeficiency syndrome

Pyomyositis, a purulent infection of skeletal muscle, is usually caused by Staphylococcus aureus. Many cases of pyomyositis in human immunodeficiency virus (HIV) seronegative patients have been reported in North America and have been reviewed extensively. Moreover, pyomyositis has been reported in association with HIV infection in patients with or without the acquired immunodeficiency syndrome (AIDS). We describe two patients with pyomyositis and HIV and review the available English language literature. Leukocytosis and bacteremia tend to occur less frequently in those with HIV infection and pyomyositis. However, fever, S aureus infection, and bilateral involvement occur more frequently in HIV-positive patients. Antibiotic therapy together with surgical drainage or aspiration is usually sufficient.

An isogenic hemoglobin receptor-deficient mutant of Haemophilus ducreyi is attenuated in the human model of experimental infection

Haemophilus ducreyi expresses a conserved hemoglobin-binding outer-membrane protein (HgbA). To test the role of HgbA in pathogenesis, we infected 9 adults with isolate 35000 and its isogenic hgbA-inactivated mutant (FX504) on their upper arms in a double-blinded, escalating dose-response study. Papules developed at similar rates at sites inoculated with the mutant or parent. The pustule-formation rate was 55% (95% confidence interval [CI], 30. 8%-78.5%) at parent sites and 0 (95% CI, 0-10.5%) at mutant sites (P<.0001). The recovery rate of H. ducreyi from surface cultures was 16% (n=142) from parent sites and 0 (n=213) from mutant sites (P<. 0001). H. ducreyi was recovered at biopsy from 6 of 7 parent sites and from 0 of 3 mutant sites. The results indicate that hemoglobin may be a critical source of heme or iron for the establishment of H. ducreyi infection in humans.

A pilus-deficient mutant of Haemophilus ducreyi is virulent in the human model of experimental infection

Haemophilus ducreyi expresses fine tangled pili, which are composed predominantly of a major subunit (FtpA). Confocal microscopy showed that an FtpA-specific monoclonal antibody bound to bacteria in biopsy samples obtained from infected human volunteers. To test the role of pili in pathogenesis, an isogenic mutant (35000HP-SMS1) was constructed by insertionally inactivating ftpA. 35000HP-SMS1 did not express FtpA and was nonpiliated but was otherwise identical to its parent, 35000HP. Seven healthy adults were challenged on the upper arm with the isogenic isolates in a double-blinded, escalating dose-response study. Sites inoculated with the mutant produced papules and pustules at rates similar to the rates observed at sites inoculated with the parent. The recovery rate of H. ducreyi from cultures and the histopathology of biopsy samples obtained from pustules inoculated with 35000HP or 35000HP-SMS1 were similar. Although pili are expressed in vivo, FtpA is not required for pustule formation in the human challenge model.

Cumulative experience with Haemophilus ducreyi 35000 in the human model of experimental infection

BACKGROUND AND OBJECTIVES

To study Haemophilus ducreyi pathogenesis, the authors developed an experimental model of infection in human volunteers. The authors analyze their cumulative experience with strain 35000 in the model and calculate the papule and pustule formation rates for estimated delivered doses (EDDs) ranging from 1 cfu to 100 cfu.

STUDY DESIGN

Sixty-five volunteers were included in the analysis. A total of 139 sites were available for calculation of the papule formation rate, and 117 sites were available for calculation of the pustule formation rates.

RESULTS

The effect of EDDs and probabilities of papule formation and the pustule formation were dose-dependent. Increasing the EDD resulted in a higher probability of papule and pustule formation.

CONCLUSION

H ducreyi is highly infectious for humans. Inoculation of an EDD of 1 cfu causes a papule formation rate of 50%. Pustule formation rates are approximately 50% for 27 cfu and 90% for 100 cfu.

Hypercalcemia as an early sign of lymphoma in a patient with acquired immunodeficiency syndrome (AIDS)

Hypercalcemia is uncommon in patients infected with the human immunodeficiency virus (HIV). It has been described in association with cytomegalovirus infection, Pneumocystis carinii pneumonia, granulomatous diseases, and lymphoma. However, symptomatic hypercalcemia as an early sign of an underlying AIDS-related lymphoma is not well documented. We discuss the case of a patient with HIV and hypercalcemia, leading to the diagnosis of an underlying lymphoma. The hypercalcemia was associated with a suppressed serum level of intact parathyroid hormone and a normal serum phosphorus level. The possibility of a lymphoproliferative disorder should be considered in the differential diagnosis of HIV-associated hypercalcemia.

Experimental infection of human volunteers with Haemophilus ducreyi does not confer protection against subsequent challenge

Two groups of human volunteers were inoculated with 2 doses of live Haemophilus ducreyi 35000HP. The reinfection group consisted of 7 subjects who previously had participated in experimental infection with 35000HP to the pustular stage of disease. The control group consisted of 7 naive subjects. Papules developed at 92.8% (95% confidence interval [CI], 66.1%-99.8%) of sites inoculated with live bacteria, in the reinfection group, and at 85.7% (95% CI, 57.2%-98. 2%) of sites in the control group. Sixty-nine percent (95% CI, 36. 8%-90.9%) of papules evolved into pustules in the reinfection group, compared with 41% (95% CI, 15.2%-72.3%) in the control group. The recovery rates of H. ducreyi from surface cultures and the histopathology of biopsies obtained from both groups were similar. Thus, experimental infection to the pustular stage of disease does not provide protective immunity against subsequent challenge.

Standardization of the experimental model of Haemophilus ducreyi infection in human subjects

Human volunteers were challenged with Haemophilus ducreyi. Twenty subjects were inoculated with 2 doses (approximately 30 cfu) of live and 1 dose of heat-killed bacteria at 3 sites on the arm. Eight subjects were assigned to biopsy 1 or 4 days after inoculation, and 12 were biopsied after they developed a painful pustular lesion or were followed until disease resolved. Papules developed at 95% of 40 sites infected with live bacteria (95% confidence interval [CI], 83. 1%-99.4%). In 24 sites followed to end point, 27% of the papules resolved, 69% (95% CI, 47.1%-86.6%) evolved into pustules, and 4% remained at the papular stage. Recovery rates of H. ducreyi from surface cultures ranged from 13% to 41%. H. ducreyi was recovered from biopsies of 12 of 15 pustules and 1 of 7 papules, suggesting that H. ducreyi replicates between the papular and pustular stages of disease.