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Year : 2018  |  Volume : 39  |  Issue : 2  |  Page : 127-129

Haemophilus parainfluenzae urethritis through orogenital transmission

1 Department of Urology, Indraprastha Apollo Hospitals, New Delhi, India
2 Department of Microbiology, Indraprastha Apollo Hospitals, New Delhi, India

Date of Web Publication7-Dec-2018

Correspondence Address:
Dr. Reetika Dawar
Department of Microbiology, Indraprastha Apollo Hospitals, Delhi-Mathura Road, Sarita Vihar, New Delhi - 110 076
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/ijstd.IJSTD_45_17

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Urethritis, which is characterized by urethral inflammation, results from infectious, traumatic, and immune sources. Amongst the infectious causes, urethritis is usually acquired through sexual route and all show similar symptoms and signs. The present case is from India of a patient with urethritis caused by Haemophilus parainfluenzae transmitted through orogenital route.

Keywords: Haemophilus parainfluenzae, matrix-assisted laser desorption/ionization time-of-flight, nonspecific urethritis, urethritis

How to cite this article:
Saxena A, Dawar R, Bora U. Haemophilus parainfluenzae urethritis through orogenital transmission. Indian J Sex Transm Dis 2018;39:127-9

How to cite this URL:
Saxena A, Dawar R, Bora U. Haemophilus parainfluenzae urethritis through orogenital transmission. Indian J Sex Transm Dis [serial online] 2018 [cited 2020 Oct 22];39:127-9. Available from:

   Introduction Top

Urethritis usually presents as mucopurulent or purulent discharge from the urethral meatus and dysuria. An itching or burning sensation in the urethra is also typical. The common organisms implicated are Chlamydia trachomatis, Mycoplasma genitalium, Trichomonas vaginalis, Ureaplasmas, Adenoviruses, and Herpes simplex viruses type 1 and 2. We report a case of acute urethritis caused by Haemophilus parainfluenzae that was initially misidentified as Pasteurella pneumotropica. This is the second report from India; first being reported in 1983[1]

   Case Report Top

A 33-year-old man presented to the urology outpatient department with a history of urethral discharge and itchy sensation for 2 weeks. There was a history of sexual contact. Three weeks prior to the development of the symptoms, the patient had unprotected insertive oral sex with a sex worker abroad. Physical examination revealed urethral discharge but no rash/papule/ulcer. The patient had got the venereal disease research laboratory test and HIV (enzyme-linked immunosorbent assay) done outside which were negative. There was no history of urethral discharge. Before his visit, the patient had been advised by a local practitioner to take Norfloxacin 400 mg twice a day for 7 days followed by amoxicillin plus clavulanate 500 mg for 7 days and fluconazole 150 mg once a day for 15 days, empirically.

The discharge was sent to microbiology laboratory for culture. It was inoculated on sheep blood agar, MacConkey Agar, and chocolate agar which was used to screen for gonococcal infection. Glistening colonies were seen on Columbia blood agar and Chocolate agar [Figure 1] along with few colonies of Coagulase-negative Staphylococcus. The glistening colonies were pale staining pleomorphic Gram-negative rods [Figure 2]. The isolate was oxidase positive, indole negative, and urease positive. On Vitek 2 Compact (BioMerieux, France), it was identified as P. pneumotropica. P. pneumotropica is a normal inhabitant of the oropharynx of mice, rats, cats, and dogs. Since there was no history of contact with animals, we put the isolate for the identification on Vitek MS (Biomerieux, France) which is based on matrix-assisted laser desorption/ionization time-of-flight technology. The isolate was identified as H. parainfluenzae.
Figure 1: Glistening colonies of H. parainfluenzae on Chocolate agar

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Figure 2: Gram stain of  H.parainfluenzae Scientific Name Search  showing pleomorphic gram negative bacilli

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Antibiotic susceptibility testing was put up by disc diffusion in accordance with the Clinical and Laboratory Standards Institute guidelines. The results showed that the isolate was sensitive to ampicillin plus clavulanate, cefotaxime, ceftriaxone, azithromycin, ciprofloxacin, tetracycline and co-trimoxazole. The isolate was beta-lactamase negative when tested by Cefinase disc.

The patient came back with discharge and no relief after the initial treatment. On detailed questioning, the patient was found to be non-compliant with the dosage as he forgot to take the antibiotics daily as per prescription and also took them for a few days only.

Antibiotics were changed to Ciprofloxacin for 15 days and Azithromycin once a day for 5 days. However, the symptoms persisted. Therefore, he was continued on ciprofloxacin for another 15 days post which he is asymptomatic till date.

   Discussion Top

Nongonococal urethritis (NGU) is one of the most common sexually transmitted diseases in men and the various known causative agents are C. trachomatis, Mycoplasma genitalium, Ureaplasma urealyticum, Gardnerella vaginalis, and Streptococcus species. Various potential viral causes cited in literature are herpes simplex virus and adenoviruses.

H. parainfluenzae is a common inhabitant of the human upper respiratory tract and a member of the normal oral microflora. H. parainfluenzae is an uncommon cause of human infections. It has been isolated from cases of endocarditis, epiglottitis, bronchitis, sinusitis, otitis media, COPD, empyema, peritonitis, and neonatal sepsis. H parainfluenzae is associated with cases of acute bacterial exacerbation of chronic bronchitis, acute otitis media, sinusitis, and pneumonia.[2]

Indistinctive clinical symptoms make it difficult to differentiate urethritis due to Haemophilus spp. from other causes of urethritis, and symptoms can vary from purulent urethral discharge to mucous clear discharge, with or without meatitis. In some cases, there may be complaints of only dysuria or urethral discomfort.

The largest study on NGU has been reported by Deza et al.,[3] of a series of 413 cases of acute urethritis in men over 2 years. In 52 cases, Haemophilus spp. was detected (12.6%). In 7 cases, Haemophilus influenzae was isolated, and in the other 45, H. parainfluenzae was isolated. In 28 cases, Haemophilus spp. was isolated as a single pathogen. Taking into account that only symptomatic patients were included and that other agents involved in urethritis were excluded, Haemophilus spp. could be consider a pathogen in at least 6.8% of the patients. The most common clinical presentation was mucopurulent urethral discharge. Patients were asked about their sexual exposures the month before consultation. All cases reported having practiced unprotected insertive oral sex, and 5 of them denied having had another sexual contact apart from this exposure. These two facts suggest that unprotected oral sex could be the main route of transmission of this pathogen. This case series highlights the potential role of H. parainfluenzae as a sexually transmitted genitourinary pathogen. 9 isolates of Haemophilus spp. were beta-lactamase producing of which all were H. parainfluenzae.

Al-Habib and Fathi[4] describes a comparative study including 240 male patients with urethritis and 40 age-matched males free from urethritis. Among these, 153 were considered as NGU cases.

H. parainfluenzae was isolated in 2.8% male patients of NGU and none in healthy controls. However, no details of their sexual histories were available. Rates of isolation vary in the literature, from 1.2% to 10%.

Hsu et al.[5] reports H. parainfluenzae urethritis in three men who had been having unprotected sex with men (MSM) in a case report from Taiwan. Two were treated with ceftriaxone and doxycycline and the third man was treated with clarithromycin. All the three patients responded to treatment.

Orellana et al.[6] conducted a cross-sectional study, in which urethral samples of 1248 men from Madrid over 3 years were analyzed. H. parainfluenzae was isolated in 1.76% and H. influenzae in 1.12%, samples. 26.47% of Haemophilus spp. were beta-lactamase-producing and all strains were susceptible to cefotaxime.

Usually. H. parainfluenzae is susceptible to third-generation cephalosporins, chloramphenicol, tetracycline and aminoglycosides. Beta-lactamase-producing strains have been reported. Oral agents used for infections where H. parainfluenzae is suspected or confirmed include penicillins, tetracyclines, quinolones, macrolides, cephalosporins, and sulfonamides.

   Conclusions Top

Haemophilus spp., especially in cases of nonspecific urethritis in men not responding to empirical therapy should be thought of in the differential diagnosis of organisms. There is circumstantial evidence that orogenital sexual practices may be linked to transmission. Most of the so called “Dhat syndrome” are treated only on clinical grounds. Some of these cases where there is a recent history of orogenital sexual contact may actually be due to H.parainfluenzae and thus a urethral swab should be sent for culture in all cases of Dhat syndrome.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.

   References Top

Chowdhury MN, Pareek SS. Urethritis associated with Haemophilus parainfluenzae: A case report. Sex Transm Dis 1983;10:45-6.  Back to cited text no. 1
Tsiplakou S, Voulalas G, Kiliari E, Kastrisios G, Maltezos C. Post-operative wound and vascular graft infection caused by Haemophilus parain fluenzae. JMM Case Rep 2015;2(3).  Back to cited text no. 2
Deza G, Martin-Ezquerra G, Gómez J, Villar-García J, Supervia A, Pujol RM. Short report: Isolation of Haemophilus influenzae and Haemophilus parainfluenzae in urethral exudates from men with acute urethritis: A descriptive study of 52 cases. Sex Transm Infect 2016;92:29-31.  Back to cited text no. 3
Al-Habib HM, Fathi HB. The role of aerobic and anaerobic bacteria in non gonococcal urethritis (NGU) in men. Ann Coll Med 2010;36:99-105.  Back to cited text no. 4
Hsu MS, Wu MY, Lin TH, Liao CH. Haemophilus parainfluenzae urethritis among homosexual men. J Microbiol Immunol Infect 2015;48:450-2.  Back to cited text no. 5
Orellana MA, Gómez ML, Teresa Sánchez M, Fernández-Chacón T. Microbiological diagnosis of urethritis in men. 3 years Review. Rev Esp Quimioter 2009;22:83.  Back to cited text no. 6


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