Retrobulbar optic neuritis and meningoencephalitis following progressive outer retinal necrosis due to CMV in a patient with AIDS

We report on a 34-year-old male patient with AIDS who developed retrobulbar optic neuritis and meningoencephalitis following bilateral progressive outer retinal necrosis (PORN) caused by cytomegalovirus (CMV). This case documents the presumed association of PORN with retrobulbar optic neuritis, and CMV meningoencephalitis in an AIDS patient.

Pulmonary tuberculosis in young Korean soldiers: incidence, drug resistance and treatment outcomes

OBJECTIVE

To determine the incidence and treatment outcomes of pulmonary tuberculosis (PTB) in young soldiers of South Korea.

DESIGN

From 2000 to 2004, all soldiers with a new diagnosis of tuberculosis (TB) were enrolled in the study, based on the official records of the Armed Forces Medical Command. The demographic and clinical data of the cases were evaluated retrospectively.

RESULTS

A total of 3115 TB cases were reported during the study period, of whom 2071 (66.5%) were reported as PTB. The annual incidence rates of PTB were 96.4 per 100,000 population in 2000, 89.3 in 2001, 67.6 in 2002, 60.2 in 2003, and 63.1 in 2004. A total of 270 patients diagnosed and treated at the Armed Forces Capital Hospital were analysed. Of the Mycobacterium tuberculosis isolates, 87.4% were susceptible to all available anti-tuberculosis drugs; 253 (93.7%) patients eventually completed initial anti-tuberculosis treatment. Among the patients with smear-positive PTB, the cure rate was 89.3% (100/112).

CONCLUSION

Our results demonstrate that the incidence of PTB in Korean soldiers, although still high, was declining steadily. With good case management, the overall success rate of initial treatment was approximately 90%.

Outcome of inappropriate empirical antibiotic therapy in patients with Staphylococcus aureus bacteraemia: analytical strategy using propensity scores

Patients with Staphylococcus aureus bacteraemia (SAB) who received either inappropriate or appropriate empirical therapy were compared by using two risk stratification models: (1) a cohort study using a propensity score to adjust for confounding by empirical treatment assignment; and (2) a propensity-matched case-control study. Inappropriate empirical therapy was modelled on the basis of patient characteristics, and included in the multivariate model to adjust for confounding. For case-matching analysis, patients with inappropriate empirical therapy (cases) were matched to those with appropriate empirical therapy (controls) on the basis of the propensity score (within 0.03 on a scale of 0-1). In total, 238 patients with SAB were enrolled in the cohort study. Characteristics associated with inappropriate empirical therapy were methicillin resistance, underlying haematological malignancy, no history of colonisation with methicillin-resistant S. aureus, and a long hospital stay before SAB. These variables were included in the propensity score, which had an area under the receiver operating characteristics curve of 85%. In the cohort study, SAB-related mortality was 39% (45/117) for inappropriate empirical therapy vs. 28% (34/121) for appropriate empirical therapy (odds ratio (OR) 1.60; 95% CI 0.93-2.76). After adjustment for independent predictors for mortality and the propensity score, inappropriate empirical therapy was not associated with mortality (adjusted OR 1.39; 95% CI 0.62-3.15). In the matched case-control study (50 pairs), SAB-related mortality was 32% (16/50) for inappropriate empirical therapy and 28% (14/50) for appropriate empirical therapy (McNemar's test; p 0.85; OR 1.15; 95% CI 0.51-2.64). In conclusion, inappropriate empirical therapy resulted in only a slight tendency towards increased mortality in patients with SAB.

A case of disseminated Cryptococcosis with skin eruption in a patient with acute leukemia

Disseminated cryptococcosis is a life-threatening infection caused by Cryptococcus neoformans and cutaneous dissemination occurs in 10-15% of patients. We report a case of a 49-y-old leukemic patient with disseminated cryptococcosis who presented with fever, headache, normal cerebrospinal fluid profile and multiple skin lesions mimicking molluscum contagiosum.

Clinical features of vivax malaria

Plasmodium vivax malaria reemerged in the Republic of Korea in 1993 near the Demilitarized Zone (DMZ). We reviewed clinical features of 101 symptomatic patients with vivax malaria. Of the patients, 77 patients (76.3%) were veterans who had served near the DMZ; their median age was 23 years. The duration of the minimum latent period was > 6 months in 66.2% (51 of 77) of the patients (median, 278 days). Tertian fever developed in 69 patients (68.3%). Severe thrombocytopenia with platelet counts < 60,000/microL was common (29.6% of patients). The parasite densities ranged 32-52,127 parasites per microliter of blood (geometric mean, 1,287). The only complication was a splenic rupture in one patient. All patients responded promptly to chloroquine therapy. Our data suggest that the clinical features of reemerging vivax malaria may be similar to those of Korean vivax malaria reported in the past.

A trial for a DNA diagnosis of Plasmodium vivax malaria recently reemerging in the Republic of Korea using microtiter plate hybridization assay

The polymerase chain reaction-based microtiter plate hybridization (PCR-MPH) assay was utilized for a DNA diagnosis of Plasmodium vivax malaria, which has recently reemerged in the Republic of Korea. The subjects were 18 parasite-proven patients and 5 healthy controls. Follow-up blood samples were collected from 4 patients after a standard course of treatment. Polymerase chain reaction and electrophoresis of all the patients' blood showed a prominent band at the 138 base pair area, but not in the controls or after treating the patients. Hybridization of the PCR products with known species-specific probes of the 18S rRNA of various malaria species revealed strong positive reactions against the Plasmodium vivax-specific probe (absorbance 1.30-1.90 at 405 nm) in all of the patients. The absorbance was positively correlated with the degree of blood parasitemia, but with a borderline significance. Sequencing of the probe region of the Korean P. vivax revealed no significant variations from the typical P. vivax. The results show that the PCR-MPH is a highly useful technique for the DNA diagnosis of Korean vivax malaria.

Evidence of two distinct subsubtypes within the HIV-1 subtype A radiation

Members of HIV-1 group M are responsible for the vast majority of AIDS cases worldwide and have been classified on the basis of their phylogenetic relationships into nine roughly equidistant clades, termed subtypes. Although there are no known phenotypic correlates for these genotypes, the disproportionate spread of certain of these lineages has been taken to indicate that subtype-specific biological differences may exist. The subtype nomenclature thus remains an important molecular epidemiological tool with which to track the course of the group M pandemic. In this study, we have characterized HIV-1 strains described previously as unusual subtype A variants on the basis of partial sequence analysis. Six such strains from Cyprus (CY), South Korea (KR), and the Democratic Republic of Congo (CD) were PCR amplified from infected cell culture or patient PBMC DNA, cloned, and sequences in their entirety (94CY017, 97KR004, 97CDKTB48, and 97CDKP58) or as half genomes (97CDKS10 and 97CDKFE4). Distance and phylogenetic analyses showed that four of these viruses (94CY017, 97CDKTB48, 97CDKFE4, and 97CDKS10) were closely related to each other, but quite divergent from all other HIV-1 strains, except for subtype A viruses, which represented their closest relatives. In phylogenetic trees from gag, pol, env, and nef regions, the four newly characterized HIV-1 strains formed a distinct sister clade to subtype A, which was as closely related to subtype A as subsubtypes F1 and F2 are to each other. According to current nomenclature rules, this defines a subsubtype, which we have tentatively termed A2. The two other viruses, 97KR004 and 97CDKP58, as well as a full-length HIV-1 sequence from the sequence database (ZAM184), were found to represent complex A2/D, A2/G, and A2/C recombinants, respectively. These results indicate that HIV-1 subtype A is composed of two subsubtypes (A1 and A2), both of which appear to have a widespread geographic distribution. The A2 viruses described here represent the first reference reagents for this new group M lineage.

Enhanced neutrophil functions by recombinant human granulocyte colony-stimulating factor in diabetic patients with foot infections in vitro

This study was performed to evaluate the effect of granulocyte-colony stimulating factor on neutrophil functions in diabetic patients with active foot infections in vitro. Twelve diabetic patients with foot infections and 12 normal volunteers were enrolled. Neutrophils from peripheral blood were incubated with granulocyte colony-stimulating factor (G-CSF, 50 ng/mL) for 20 min. Superoxide production of neutrophils was measured by the reduction of ferricytochrome C. Neutrophil phagocytosis was assayed using Staphylococcus aureus and the weighted phagocytic index was calculated. Superoxide production of neutrophils in diabetic patients with foot infections was 7.7 (unit: nmol/2 x 10(5) cells/60 min), which was significantly lower than that in controls (12.0) (p<0.05). G-CSF increased neutrophil superoxide production to 12.1 in diabetic patients with foot infections and to 19.8 in controls (p<0.05 for each). Weighted phagocytic index in diabetic patients with foot infections was 0.77, which was not significantly different from that of the controls (0.69). Weighted phagocytic index was increased significantly by G-CSF to 0.88 in diabetic patients with foot infections and to 0.79 in controls (p<0.05 for each). In conclusion, G-CSF significantly enhanced neutrophil functions in diabetic patients with foot infections in vitro.

Naturally acquired antibody responses to the C-terminal region of merozoite surface protein 1 of Plasmodium vivax in Korea

We expressed a protein in Saccharomyces cerevisiae in order to evaluate the humoral immune responses to the C-terminal region of the merozoite surface protein 1 of Plasmodium vivax. This protein (Pv200(18)) had a molecular mass of 18 kDa and was reactive with the sera of individuals with patent vivax malaria on immunoblotting analysis. The levels of immunoglobulin M (IgM) and IgG antibodies against Pv200(18) were measured in 421 patients with vivax malaria (patient group), 528 healthy individuals from areas of nonendemicity (control group 1), and 470 healthy individuals from areas of endemicity (control group 2), using the indirect enzyme-linked immunosorbent assay (ELISA) method. To study the longevity of the antibodies, 20 subjects from the patient group were also tested for the antibody levels once a month for 1 year. When the cutoff values for seropositivity were determined as the mean + 3 x standard deviation of the antibody levels in control group 1, both IgG and IgM antibody levels were negative in 98.5% (465 of 472) of control group 2. The IgG and IgM antibodies were positive in 88.1% (371 of 421) and 94.5% (398 of 421) of the patient group, respectively. The IgM antibody became negative 2 to 4 months after the onset of symptoms, whereas the IgG antibody usually remained positive for more than 5 months. In conclusion, indirect ELISA using Pv200(18) expressed in S. cerevisiae may be a useful diagnostic method for vivax malaria.

The frequency of mutation in CCR5 gene among Koreans

To better understand a role of the delta32 allele of the CCR5 gene in HIV-1 transmission and disease progression, we determined the CCR5 genotypes within several groups of Koreans. Amplification of DNA from each subject was achieved with polymerase chain reaction, using the CCR5 specific primer pair, which flanks the 32 bp deletion. The 1.2 kb coding sequences of CCR5 were examined to see the possible effects of CCR5 polymorphism. All of the 339 healthy, HIV-uninfected individuals had no mutation in the CCR5 gene. All of the 115 HIV-1-infected patients including 11 long-term non-progressors (LTNPs) and 18 discordant spouses were also wild homozygotes. No variation in the 1.2kb CCR5 coding sequence was found in 5 LTNPs and 5 discordant spouses. In conclusion, the 32 bp deletion mutant is rarely present in Koreans. Our data suggest that factors other than the CCR5 coding sequences may also play a role in the resistance to HIV infection.

Induction and maintenance treatment regimens for HIV-1 infection in vitro

Can aggressive anti-human immunodeficiency virus (HIV) induction regimens be simplified after sufficient virus suppression is achieved? In vitro studies were conducted to evaluate the hypothesis that aggressive induction regimens could be followed by less aggressive maintenance regimens. A clinical HIV-1 isolate and lymphoblastoid cell line (H9) were employed. Virus multiplicities were varied, as were drug inhibitory concentrations (IC90, IC99) and induction periods (1, 2 and 3 weeks) of a three-drug regimen (zidovudine plus lamivudine and indinavir), following which maintenance regimens (no drug, zidovudine alone, indinavir alone, zidovudine plus lamivudine) were employed. After 1 week inductions at IC99 concentrations, viral rebound occurred on none or one-drug maintenance regimens but not on a two-drug regimen. After 2 week inductions, viral rebound occurred with no-drug maintenance, but not with one- and two-drug regimens. After 3 week inductions, viral rebound did not occur in zero-, one-, or two-drug maintenance regimens, although HIV-1 DNA persisted in cultured cells. These studies suggest that although some induction-maintenance regimens will fail, after a sufficient period of HIV-1 suppression with a three-drug antiretroviral regimen, maintenance on fewer drugs may be feasible.

Spectrum of opportunistic infections and malignancies in patients with human immunodeficiency virus infection in South Korea

To determine the frequency and types of major opportunistic diseases in patients with HIV infection in South Korea, we reviewed the medical records of 173 HIV-infected patients. The patients were seen from 1985 to 1998 at a referral hospital for AIDS in South Korea. Most patients (85%) were male, and 107 (62%) were infected by heterosexual contacts. CD4+ lymphocyte counts at presentation were <200/microL in 27% of the patients. Tuberculosis was the most frequent opportunistic infection (25% of patients), followed by candidiasis (21%), herpes zoster (20%), Pneumocystis carinii pneumonia (10%), cytomegalovirus disease (9.8%). There were no cases of toxoplasmosis. Kaposi's sarcoma developed in 3 patients (1.7%), and non-Hodgkin's lymphoma, in 2 (1.2%). Eleven patients (6.4%) developed peripheral neuropathy, and 8 (4.6%) had HIV encephalopathy. Tuberculosis was the single most important HIV-related infection in South Korean patients.

Epidemiology of HIV infection in the Republic of Korea

Since the first case of human immunodeficiency virus (HIV) infection in the Republic of Korea (ROK) was detected in 1985, 876 HIV-infected patients have been reported, as of December 1998. The male to female ratio was 6.8:1, and 87% of the patients were between 20 and 49 years of age. The major modes of transmission were sexual contacts, accounting for 86% of the cases (65% heterosexuals and 21% homosexuals). Transmission through blood and blood products accounted for 28 cases (3.2%), and vertical transmission for one case. No cases among intravenous drug abusers were reported. The seroprevalence among the blood donors was approximately one in 100,000. Subtypes A, B, C, D, E, and G of HIV-1 have been introduced into the ROK, and subtype B is the most predominant subtype. The frequency of the a deletion in the CCR5 gene, a coreceptor of HIV-1, was less than 1% among Koreans.

Epidemiological typing of methicillin-resistant Staphylococcus aureus outbreak isolates by pulsed-field gel electrophoresis and antibiogram

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common nosocomial pathogens. In April 1997, there were five MRSA-infected patients among 16 patients in the Neonatal Intensive Care Unit (NICU), Seoul National University Hospital, which is a tertiary-care hospital with 1,500 beds. The infections had spread from twin patients with MRSA who had transferred from Hospital C. MRSA was isolated from the axilla of 15 (94%) of the 16 patients, including the two patients with obvious infections. Three (19%) of 16 doctors and nine (30%) of 30 nurses had MRSA colonization of the anterior nares. Six different PFGE patterns (A through F) were identified in the 53 isolates of MRSA tested. Twelve of 13 isolates from infected sites of five patients showed pattern F. Three MRSA strains obtained from hospital C showed closely or possibly related pattern F. MRSA of type F was isolated from three of 16 patients' axilla, and one of 3 doctors' and three of 30 nurses' nasal swabs. The antibiogram code for 12 of 13 MRSA isolates from five infected patients was 66,754. PFGE patterns of these isolates were either F, F1, F2 or Fa. Only one of three strains isolated from clinical specimens of patients in Hospital C showed the antibiogram code 66754, although they were all PFGE types F1 and Fa. In conclusion, the presumptive sources of the outbreak of MRSA infection in NICU were the twin patients transferred from hospital C. Antibiogram correlated reasonably well to the PFGE type. An effective notification system is needed when a MRSA-infected patient is transferred to another hospital to control the spread of the infection.

Association of specific amino acid sequence of HLA-DR with rheumatoid arthritis in Koreans and its diagnostic value

OBJECTIVE

To analyze the association of susceptibility epitopes and alleles of HLA-DRB1 with rheumatoid arthritis (RA) in Koreans.

METHODS

We performed HLA-DRB1 epitope typing in 61 patients and 82 controls using polymerase chain reaction (PCR) oligonucleotide hybridization, and HLA-DR4, DR1, and DR8 alleles were characterized by PCR single strand conformation polymorphism (SSCP).

RESULTS

The frequency of HLA-DR4 was significantly increased in patients with RA compared with controls (61 vs 29%; RR = 3.7, p < 0.0001). Epitope analysis revealed that susceptibility sequences in Korean patients with RA were 70QRRA74A (52 vs 21%; RR = 4.2, p < 0.0001) and 70QKRA74A (10 vs 1%; RR = 8.8, p < 0.05). The frequency of patients carrying either QRRAA or QKRAA at the 70-74 position on the HLA-DR beta 1 molecule was significantly increased compared with controls (57 vs 22%; RR = 4.8, p < 0.0001). Genotypical analysis showed that DRB1*0405 and *0401 were the DR4 alleles associated with RA in Koreans (RR = 9.4, p < 0.00005; RR = 8.8, p < 0.05, respectively). No significant differences were noted for other alleles including DRB1*0404 and DRB1*0101. QRRAA epitope typing was considered to have some diagnostic value for early RA.

CONCLUSION

Our observation indicates that a shared sequence 70QR(K)RA74A, especially in HLA-DR4 subtypes, is strongly associated with RA in the Korean population. Additionally, the importance of DRB1*0405 in the pathogenesis of RA in East Asian ethnic groups was confirmed. These data suggest that not only the specific amino acid sequences but also the whole structure of the HLA-DR beta 1 molecule are important with regard to susceptibility to RA.

Association of complement alleles C4AQ0 and C4B5 with rheumatoid arthritis in Koreans

OBJECTIVE

To investigate the association of complement C4 allotypes with rheumatoid arthritis in Koreans.

METHODS

65 rheumatoid arthritis patients and 255 controls were typed for C4 allotypes and HLA-A, B, C, DR, and DQ antigens.

RESULTS

The frequencies of C4AQ0 (32.3% v 14.9%, P < 0.005) and C4B5 (29.2% v 12.2%, P < 0.005) were significantly increased in rheumatoid arthritis patients compared with healthy control subjects. Among rheumatoid patients, the frequency of C4AQ0 was significantly increased in both the rheumatoid factor (RF) positive (27.3%) and the RF negative (66.7%) subgroups. The frequencies of C4B5 and HLA-DR4 were significantly increased only in RF positive subgroup. C4B5 was strongly associated with HLA-DR4, whereas C4AQ0 did not show association with DR4.

CONCLUSIONS

In Koreans, C4AQ0 and C4B5 are associated with susceptibility to rheumatoid arthritis, as in the Japanese. C4B5 is strongly associated with HLA-DR4. C4AQ0 is considered to be a DR4 independent risk factor, and a disease susceptibility allele in linkage disequilibrium with C4AQ0 is suggested in Korean patients with rheumatoid arthritis.

Infections in acute leukemia: a retrospective study of 148 patients

To study the nature, offending organisms, consequence, and prognostic factors of infection in acute leukemia, we reviewed the cases of 148 patients admitted to the internal medicine service at Seoul National University Hospital between December 1980 and June 1984. The findings are summarized as follows: (1) The total number of infections was 143, 54% of which occurred after anti-cancer chemotherapy (induction; 28%, maintenance; 14%, reinduction; 10%, consolidation; 2%). Fifty-one percent responded to therapy, and 24% expired due to infection (13%) or other causes (11%). (2) Sixty-four percent of the infections occurred during a granulocytopenic episode (>500/mm³), whereas 36% occurred in the absence of granulocytopenia. When induction, reinduction or consolidation chemotherapy was instituted, infection occurred in 85% of the cases in which granulocytopenia had developed (n=59) and in 50% of the cases in which granulocytopenia had not developed (n=14). (3) Microbiologically documented infection, clinically documented infection and, possible infection accounted for 19%, 47%, and 34% of the total infection episodes, respectively, and in microbiologically or clinically documented infection (n=95), mortality due to infection was 19%, compared to 2% in possible infection (n=48), which was significantly lower (P<.005). Gram negative and positive bacteria accounted for 71.4% and 25.0% of the microbiologically documented infection, respectively, and Pseudomonas species, E. coli, and Staphylococcus aureus were the most common pathogens. Pharyngitis was the most common type of infection to be followed by skin and soft tissue infection, pneumonia and primary septicemia, etc. (4) Eighty-eight and two tenths percent of the patients with bone marrow recovery responded to therapy, a percentage significantly higher than 46 5% for those whose bone marrow function was not restored (P<.005)